Waves of ambition: Russia’s military build-up in Crimea and the Black Sea

Russian military carrying out JSE-Zapad-2021 exercises at the Mulino training center, September 2021
Summary available in


  • Russia’s capacity to carry out large-scale military operations against Black Sea states allows it to coerce and extort them.
  • Reducing the predictability of such operations is the first step towards deterring them, because Moscow carefully weighs their risks.
  • Western countries should increase their militaries’ interoperability with Black Sea states’ armed forces and improve the infrastructure they use to deploy reinforcements in the region.
  • This would allow them to react to Russian military escalation in kind and thereby increase the risks for Moscow.
  • With Ukraine and Georgia engaged in land wars against Russia, the vulnerabilities of Ukrainian and Georgian airspace and territorial waters have received relatively little attention.
  • Western states could begin to address these vulnerabilities by establishing an international naval presence in the Black Sea.
  • This would counter Russia’s attempts to deny other nations free use of the sea, and could help mitigate long-standing rivalries between allied states in the region.
  • These efforts to enhance Black Sea states’ security will depend on improvements in other areas, particularly the security of government communications, counter-intelligence, the rule of law, and the fight against corruption.


On 18 March 2014, Russian forces in Crimea staged a referendum to try to legitimise their permanent occupation and annexation of the peninsula to the Russian Federation. The troops had been moving into Crimea since 27 February, after so-called volunteers took control of government buildings there. Soon, Russia would instigate other incidents in Ukraine: in Odessa, Luhansk, Sloviansk, Kharkiv, and Donetsk, pro-Russian action groups – supported and organised by Russia’s military intelligence services – tried to incite further revolts against the government in Kyiv. They were supported by clandestine military operations designed to break up Ukraine.

While these events are well documented, Ukrainians’ reaction to them receives little attention in the West. The dominant narrative on the crisis is that the interim government that took over after President Viktor Yanukovych fled the country needed time to take charge of its duties – and that Ukraine’s military and law enforcement agencies, being in a dismal state, were largely unable to react to the swift Russian military intervention.

While this is true, it is only a part of the picture. By mid-March 2014, Russia had already assembled troops on the Ukrainian-Russian border. And, by mid-April, the West was speculating about the prospect of a full-scale invasion. The Russian military build-up was reinforced by the mobilisation of personnel from the Russian ‘power’ ministries – the Ministry of the Interior and the Ministry of Emergency Situations – who would be suitable for tasks they would carry out as occupying forces. Hence, at the time, Kyiv feared the worst, and there was little that it or the West could have done to foil Russia’s plans (especially at short notice).

Crimea annexation: map of Ukrainian and (anticipated) Russian troop movements

The Russian forces grouped in three operative manoeuvre groups – one close to the Russian-Belarusian border, one in Belgorod, and one in Rostov-on-Don. One could easily guess these groups’ operative directions from their locations: the first would move on Kyiv, the second on Kharkiv, and the third on Donbas. Geographically, Ukraine was in a similar situation to Poland in 1939: the attacker was not only stronger and technologically superior but also started from a position that would enable it to circumvent and encircle any military opposition close to the border. In an all-out confrontation with Russia, Ukraine would have had no chance.

The Ukrainian government chose to deploy the small number of its military forces that were combat ready to defend Kyiv. This was the most prudent decision given the overall situation – it would have allowed the government to delay the Russian advance into western Ukraine and buy time to call for international assistance. If the forces were deployed further to the east, they would be in an exposed position. In the event of a full-scale invasion, they would be encircled. The Ukrainian state would probably cease to exist in its current form if Russia had captured Kyiv.

However, this approach meant that the few Ukrainian security forces in the east (police and Ministry of Interior forces, some of which had disbanded following the revolution) were on their own. They had no units prepared to prevent the takeover of administrative buildings by ‘separatist’ forces, comprising organised crime groups backed by Russian special operations soldiers. Russia made use of the vacuum – the war in Donbas had started.

The crisis showed how Russia could influence other states’ behaviour simply by threatening a full-scale military invasion. Such an invasion of Ukraine never happened, but the threat of one had a tangible impact on history. Was the full-scale invasion of Ukraine likely, or was Russia just bluffing? It is impossible to know how Russia would have reacted if the Ukrainian government had chosen to reinforce Donbas and leave Kyiv vulnerable, betting on a Russian bluff.

Russia repeated its military build-up and sabre-rattling at Ukraine in spring 2021, showing that military force continues to be one of the key foreign policy tools that the Kremlin uses against Kyiv. This time, the strategic objective of the Russian threat seemed rather limited: forcing Kyiv to comply with Moscow’s conception of the Minsk agreements. But, given that Russia views these accords as a means to divide (and rule) Ukraine, its overall goal has not changed since 2014.

Some EU countries, particularly France and Germany, seem to dismiss the chances of a full-scale Russian invasion of Ukraine, sticking with their diplomatic routine of issuing statements of concern, calling on both parties to de-escalate, and reminding everyone that the conflict can only be resolved by diplomatic means. Yet this approach underestimates the dangers inherent in Russia’s military moves.

While the Ukrainian case is the most recent and obvious example of Moscow’s military strength tangibly affecting other states’ policies, the same dynamic applies to other countries in the vicinity of Russia. And, with the military build-up in Crimea that followed the annexation, Russia has dramatically broadened its military options in relation to all Black Sea littoral states. This puts Moscow in a position to use implicit and explicit military threats to influence their domestic affairs.

European leaders need to stop treating military power as a relic of the past and any prospect of Russian military escalation as “unthinkable” or “unwise”. Too often, they have pretended to know what the Kremlin’s interests ought to be, causing them to misjudge the extent to which it will use force to achieve its goals. This paper aims to help European policymakers understand what is at stake and what may happen if deterrence fails. It also seeks to address some of the Black Sea states’ most urgent vulnerabilities.

Not all the scenarios discussed in this paper are likely to happen regularly – nor are they necessarily Russia’s preferred outcome. But they are all realistic and in line with the respective armed forces’ range of capabilities. Moscow can use its military options to threaten and influence domestic debates in the countries it targets. Policymakers in the West will need to prepare for these scenarios one way or the other – not least because, if Moscow slowly explores its options and pushes towards such scenarios, it may go ahead with them unless Europe or the United States signals that it would face resistance.

If the West was to seriously prepare for a broad range of military contingencies in eastern Europe, it would be able to deter Russia from using military force there. This paper explains how these scenarios could unfold to undermine stability in Russia’s neighbourhood. The paper does not argue that Russia will immediately make all these moves – which will largely depend on the diplomatic and political situation at the moment of crisis – but that such scenarios concern defence planners in the region and have a tangible impact on policymaking there.

When would Russia go to war?

Discussing every instance in which Russia would go to war could fill an entire book. However, it is important for European policymakers to understand some of the most likely scenarios in which Moscow would resort to military force in the Black Sea region.

Firstly, for Russia, the capacity to use military coercion against one’s neighbours is a key attribute of any great power. Military superiority is a goal in itself, irrespective of whether one intends to act. In the Kremlin’s view, other states’ vulnerability to the Russian military should make them fear it and, accordingly, respect Russian interests. Much of this perception stems from the Kremlin’s projection of its own preoccupation with military affairs onto other countries. In reality, states that are militarily vulnerable to or dependent on Russia – particularly Ukraine, Georgia, and Armenia – often act independently, confusing the Kremlin with their ability to ignore its might.

Moscow combines this preoccupation with a stubborn resistance to intelligence on the politics of neighbouring states that contradicts its preconceptions, often leading it to suspect that the West provides covert military backing for these states’ so-called anti-Russian behaviour. As a consequence, Russian leaders sometimes talk themselves into a spiral of escalation that is based only on their own imaginations but that can have tragic consequences in the real world, particularly for neighbouring states.

Indeed, Europe has witnessed such a spiral over the last decade: Moscow increased the pressure, interference, and blackmail it directs against its neighbours to enforce its demand for pre-eminence in the post-Soviet space. The more it did so, the more states and societies within that space started to look to the West to resist that pressure.

But, despite these setbacks, Moscow has not yet changed its main foreign policy objective: to restore its control over post-Soviet countries, particularly Ukraine, and deter the West from interfering in the process. To that end, Moscow employs military coercion (including implicit and explicit nuclear threats), diversionary attacks across many domains (ranging from the electoral process to cyberspace), and aggressive information warfare to prevent the West from engaging with states that Russian leaders perceive as geopolitical pawns.

Whether Russia will make good on its threats and aggressive signalling is another matter. While the Kremlin wants to create the impression that it is mighty, aggressive, and daring, it tends to back off once the risks become either too big or unpredictable. Russia toned down the war in Donbas once initial battles showed that a summer offensive in 2015 would come at too high a price. It ended its spring 2021 sabre-rattling once it was clear that it could make no further gains, and that blackmail through escalation could trigger a Western response that would threaten Russia’s interests.

The other often underestimated factor in whether Moscow would go to war is the predictability of its military efforts. To Western leaders (particularly Europeans), occupying Crimea and starting a clandestine military campaign in Donbas may seem bold and daring. But Russia was certain about the outcome of the Crimean campaign, due to its penetration of the Ukrainian political and security apparatus at the time, the presence of its Black Sea Fleet in Sevastopol, and its ability to read Ukrainian government and military communications. The situation in Donbas was less clear, calling for greater caution.

Likewise, in Syria, Moscow tested the West’s resolve and willingness to enter the war in the three years before it intervened. And, given the Assad regime’s decades-long military cooperation with the Soviet Union and then Russia, Syria was familiar territory for Russian leaders.

Western defence planners should remember that Moscow wants to measure its chances of success as best it can before acting, as shown in the Russian intelligence services’ relentless effort to penetrate neighbouring states’ security and political systems. Therefore, denying Moscow this advantage is the first step towards successful deterrence.

While Russia’s security elites regard the US as the main enemy, their grand strategy to defeat this enemy is still somewhat elusive. The Kremlin tries to tie down the West by widening political divides in the US and Europe, carrying out diversionary attacks, and supporting all sorts of anti-Western movements and armed groups around the globe. While it is not powerful enough to confront the West head-on, Russia will target any vulnerability that presents itself – where even a weak punch may disable the opponent.

It once seemed that a limited Russian offensive in the Baltic states – designed to show that the US would not live up to its security commitments – was the most likely scenario in which Russia and NATO would slide into war. However, the Baltic states are no longer Europe’s main vulnerability. The West also faces the predicaments of geography, distant reserves, and Russian forces’ time advantages in the Black Sea region. One can dispute how likely such scenarios are, and what circumstances could lead to them – such as a war in the Pacific distracting the US, Tucker Carlson winning the US presidential race in 2024, and so on – but it is important for European leaders to understand how authoritarian powers could exploit a crisis in the region.

The Russian military build-up in Crimea

By 2014, much of the military infrastructure in Crimea – airports, radar stations, bunkers, and barracks – had decayed. Ukraine did not perceive Crimea as a priority or prepare to fight for it. Nor did it perceive any other Black Sea state as a likely enemy. Of course, this changed after the Russian annexation of the peninsula.

Officially, Russia worries about a Ukrainian counter-strike – the chances of which are remote. But, in practice, Russia uses Crimea as a platform to militarily dominate the Black Sea and its littoral states. The land connection between Ukraine and Crimea can be defended by a small force. And Ukraine lacks the capacity to conduct an effective amphibious assault on Crimea. Hence, from a defensive point of view, there is little to no need for a large military presence in Crimea. But, as the Russian military’s thinking is inherently offensive and pre-emptive, its approach to defending the peninsula requires coercion and domination of the Black Sea region.

Russia currently operates the following forces in Crimea:

Russian ground and coastal defence forces in Crimea

As well as the following aviation units:

Active airbases  and units

Russia has modernised and expanded the Black Sea Fleet faster than any of its other fleets. The Black Sea Fleet’s large surface combatants, the Soviet-era guided-missile cruiser Moskva and two Krivak-class frigates, have been joined by three new Admiral Grigorovich-class guided-missile frigates (a fourth is being built). The fleet’s Kilo-class submarine has been joined by six modernised ones, and its small craft and patrol vessels have roughly doubled in number, since 2014. Of these, three Buyan-M-class missile crafts can carry up to eight Kalibr cruise missiles. The Black Sea Fleet includes three Alligator-class and four Ropucha-class landing ships, which can collectively land up to 160 armoured fighting vehicles (depending on their size and weight) on enemy beaches. These vessels have been busy shipping Russian military equipment and, later, troops to Syria throughout the Syrian civil war, which began in 2011. Another significant capability of the fleet is its four intelligence gathering ships, including the Ivan Khurs – which, completed in 2018, is the most modern vessel of this kind in the Russian Navy.

Russia can reinforce the Black Sea Fleet with ships from the Caspian Flotilla, via the Volga-Don Canal. Among these potential reinforcements, two Gerard-class frigates and six Buyan-class corvettes (half of which can launch Kalibr cruise missiles) would add considerable firepower. The flotilla’s one Dyugon-class, one Akula-class, and six Serna-class landing craft have only a small transport capacity but are well suited to navigating shallow waters. Hence, they can access much of the coast of the Sea of Azov that larger landing craft cannot.

The long-range strike capabilities of these two fleets are what bothers NATO planners most. The Kalibr has a range of roughly 2,500km and is capable of carrying nuclear warheads. From the well-protected waters around Crimea, Russia can launch nuclear strikes against targets in most of Europe, with Paris and London being at maximum range. Russia’s deployment of roughly 48 land-based 9M729s (the land-mobile version of the 3M54 Kalibr) led to the end of the Intermediate-Range Nuclear Forces Treaty and much diplomatic tension between the West and Russia, but the total launch capacity of the two fleets is almost three times this number.

Crimea’s role as a staging area from which to threaten parts of Europe, and to communicate this threat as part of a wider escalation-control effort, has strategic consequences far beyond the Black Sea region. (There are other dual-capable weapons systems deployed to Crimea that could, in theory, carry nuclear warheads – including anti-ship cruise missiles, air-defence missiles, artillery rockets, and short-range ballistic missiles – but, due to their limited range or lack of land-attack capability, they do not play the same strategic role as the Kalibr). Russia’s renovation and restoration of the nuclear weapons storage sites at Krasnokamenka base (Feodosia-13) heightens Europeans’ fear that Russia will use Crimea to forward-deploy these systems. Storing them relatively close to their intended launchers would reduce the warning time for the West in the event of an attack.

Therefore, Russia’s current conventional military posture is already far beyond a defensive one. While it is still too small or lacking the amphibious capacities to quickly conquer any other Black Sea states, the force is capable of conducting raiding operations: its mixture of intelligence, deep-strike, and highly mobile forces – special forces, marines, and air-mobile troops – allows for swift amphibious and airborne assaults to surprise and stun an enemy. However, these forces could run into difficulties supporting sustained operations across the Black Sea that required larger armoured ground formations, as this would create logistical bottlenecks in shipping and airlift capacity.

But such bottlenecks could be temporary. Even open-source satellite pictures reveal intensive work on several military bases and installations on the occupied peninsula. (As some of the publicly available pictures of these facilities are several years old, Russia might have already completed or expanded much of the construction and renovation work on them). A preliminary list of the facilities undergoing or awaiting reconstruction includes:

Military facilities undergoing renovation and reconstruction

Russia’s military infrastructure reconstruction outpaces any civilian development programme on the peninsula. This is particularly striking given that water and electricity shortages continue to plague the economic and social development of Crimea. But Moscow has its own priorities.

Even by its current standards, Russia has an excessive amount of military infrastructure on the peninsula relative to the size of the forces permanently based there. There is unlikely to be a dramatic rise in the number of military formations permanently deployed to Crimea. For example, the Tu-22M3 bombers rumoured to be deployed to Novofedorivka airbase have not been deployed there outside of exercises (because this would draw them away from bases closer to their daily training and operational routine routes). But the military infrastructure exceeding current needs enables Moscow to rapidly increase its military presence by deploying forces from other regions. In a crisis, Crimea would serve as a platform from which to project military power across the region.

Russia provided a glimpse into what to expect in this scenario by conducting snap exercises and troop deployments in Crimea and on Ukraine’s borders in March and April 2021. Again, airborne and air-mobile forces featured prominently in the order of battle, pointing towards their special role in any invasion or raiding force. The exercises Russia held in Crimea at the time involved a rapid airborne assault on an enemy airfield, which it then used to fly in further reinforcements. European policymakers need to understand the strategic context in which Russia could conduct these kinds of lightning raids.

Contingencies and military options

The military assets described above provide Russia with plenty of options to use military force in the Black Sea region. But they are not a defensive countermeasure to Western moves – despite claims to contrary from Russia and some Western analysts. For example, there was little threat to Russia from the US-led Defender-Europe 21 exercise, which took place after the Russian military build-up on Ukraine’s borders in April and May this year. The exercise may have involved 28,000 soldiers from NATO and a few neutral countries but it focused on logistics and deployment to the entire Balkan Peninsula. While logistics and deployment are crucial to any military operation, only around 1,000 soldiers in combat forces deployed to Romania and Bulgaria each during the course of the exercise. According to Valery Gerasimov, the Russian army’s chief of staff, around 300,000 soldiers took part in the deployment on Ukraine’s borders. Experts estimate that between 80,000 and 120,000 of these were combat troops (with depot and logistical staff probably accounting for the rest). In contrast to Defender-Europe 21, the manoeuvres these forces engaged in were a form of coercive diplomacy and power projection. And such Russian operations in the Black Sea region are not confined to Ukraine. There is also a risk that Russia could use military coercion in Georgia and in hybrid incursions into NATO and EU territory.

Operations against Ukraine

Ukraine seems to be the most likely target of heightened Russian aggression, as indicated by the war scare in March and April 2021. But the incident also pointed towards some of the limitations of Crimea as a staging area for an effective military assault on Ukrainian-controlled territory. The occupied peninsula is separated from the rest of Ukraine by swamps, lagoons, and waterways that many Russian forces could only cross following extensive preparation by combat engineers. These obstacles would slow an advance by heavy mechanised forces and would provide Ukrainian artillery with plenty of stationary targets. The Black Sea Fleet’s amphibious capacities are still limited, furthermore, by the shallowness of the edge of the Sea of Azov, which provides only a few spots in which heavy landing ships could disembark troops. Russia could conduct amphibious operations on Ukraine’s Black Sea shore proper, but the weakly reinforced regiment that it could bring ashore would only have military value if it served as a diversion or as support for a land-based assault from Ukraine’s eastern or northern border. Otherwise, Ukraine’s reserves – particularly the high-readiness 45th Air Assault Brigade, stationed at Bolhrad, in Odessa oblast – would be ready to deal with it.

A diversionary force may still be of military use, especially if Moscow intends to raise the stakes in the war in Donbas through escalation and wants to tie down as many Ukrainian reserves as possible. This was presumably the aim of the operation to assemble forces in Crimea and around Voronezh in spring 2021. And air assets based in Crimea could operate against Ukraine irrespective of obstacles on land and sea.

Crimea plays a key role in Russian policy designed to pressure Ukraine short of full-scale war. The Sea of Azov dispute is the most prominent example of this: viewing the sea as a Russian inland waterway and hence its territorial waters, Russia prevents other countries’ navies – and often their commercial freighters – from accessing it. Russia built the Kerch Strait bridge to stop ships taller than 33m from passing through, severely restricting the size of freighters that can cross the Sea of Azov to the Ukrainian ports of Mariupol and Berdyansk.

Moreover, Russia uses its rule over Crimea and its coastal patrol and maritime security powers to delay or entirely cut off naval transport to Ukrainian ports, by denying passage through the Kerch Strait. It also restricted Ukraine’s use of the Sea of Azov by detaining Ukrainian fishermen and other commercial actors. Since March 2021 – and presumably at least until October 2021 – Russia has blocked access to the Sea of Azov entirely, citing “manoeuvres” as a reason to ban all but Russian naval vessels from approaching the Kerch Strait. Those manoeuvres occurred in March and April, during the war scare. But Russia left the restrictions in place to prevent Ukraine from exporting the grain and corn harvest through Mariupol and Berdyansk. This will have lasting economic consequences for large parts of Ukraine.

To challenge Moscow’s infringement of access to the Sea of Azov, Ukraine brought a case against Russia before the International Court of Arbitration, where it is set to run until at least 2022. Once the case is concluded, Russia will most likely ignore the verdict and continue to blockade Ukraine. This would set a dangerous international precedent, particularly with regard to China – which, by claiming exclusive control over the South China Sea, has shown a similar indifference to maritime law. Indeed, Beijing has lost a maritime case before the International Court of Arbitration, which it seems happy to ignore.

In the meantime, the blockade on Ukraine places a heavy economic burden on the areas of Donetsk still under Ukrainian control. Industries there are heavily reliant on export through the ports. The railway system in the region is geared around its hub in Donetsk city, which is now occupied by Russia. The European Union has pledged to support Kyiv in expanding the road and rail infrastructure serving Mariupol. But shipping is the most efficient method of transport for sectors such as steel, railcars, specialised machinery, and heavy industry.

Even if Ukrainian firms divert their exports through Odessa in future, Russia would be in a position to blockade the port there as well. In 2014 Russian special operations forces took control of Ukraine’s oil- and gas-extraction platforms in the Black Sea, which stretch out westwards to the Crimean peninsula. Russia occupies not only installations close to Crimea’s shores but all former Ukrainian ones, including oil rigs off the Romanian coast. These facilities have been heavily guarded since then, with Russian Black Sea Fleet and Federal Security Service (FSB) border patrol vessels warning off any ship that comes too close. Under the pretext of security concerns, Russia could extend the restrictions to the Ukrainian coast, thereby completing the naval blockade. In addition, Russia has installed surveillance sensors on these platforms, spying on surface and undersea maritime traffic off the Ukrainian coast.

On its own, Ukraine can do little in response to Russia’s aggressive behaviour. In November 2018, a Ukrainian tugboat and a group of patrol craft tried to pass through the Kerch Strait into the Sea of Azov to underline Ukraine’s right to access its own ports. They were attacked, boarded, and captured in international waters before even coming close to the Kerch Strait. The assault on them – conducted by naval vessels and aerial assets based in Crimea, and backed by electronic warfare, air defence, and coastal missile units on the peninsula – showed both Russian’s escalation dominance and that any deployment of Ukrainian fighters in response would have faced an attack from Crimea. The Kremlin would interpret any Ukrainian engagement with a land-based asset in Crimea as an attack on Russia proper, and hence a pretext for all-out war.

This is why international naval patrols to Odessa are vital to underscore Ukraine’s right to access its ports. Attacking or driving off US or European vessels in a similar manner would have graver implications. However, Russia is increasingly testing them as well, continuously pushing the boundaries of what the West will tolerate. When NATO vessels call on Ukrainian ports, Russia suddenly announces live-fire manoeuvres and related closures to impede their operations. And Russia aggressively deploys aircraft and ships trying to force other vessels away from waters close to Crimea. Effectively, Moscow wants to turn the Black Sea into a no-go area for the West. None of this is necessary for the defence of the peninsula. Moscow’s approach is designed to deprive Kyiv of international support, increase Russian leverage over Black Sea states, and enforce Russian dominance over the region.

Operations against Georgia

While the conflict in Ukraine has gained international prominence, it is not the only war Russia is waging in the Black Sea region. Since the five-day war in Georgia in August 2008, the tensions between Moscow and Tbilisi have primarily come from Russia’s “borderisation” of South Ossetia and Abkhazia – breakaway regions that it occupies, supplies, and manages. At times, FSB border guards push the border fence a few metres into Georgian-controlled territory to arrest or otherwise harass people, and arbitrarily close the border to inhibit the little remaining cross-border traffic.

While these incidents certainly stir up unease among Georgians, Moscow can rely on Georgia’s domestic politics to prevent the country from drawing closer to the EU or NATO of its own accord. The Georgian Dream party has captured the state and refuses to reform; hyper-partisanship prevents any cooperation across the political spectrum; mutual accusations of political obstruction and election fraud abound; and oligarchic economic structures infringe upon judicial independence and otherwise undermine the rule of law. The EU brokered in April an agreement to overcome the post-electoral political crisis, but this is now defunct. The activation in July 2021 of an old cooperation agreement between the State Security Service, Georgia’s domestic intelligence agency, and the Belarusian KGB made a mockery of the Georgian government’s claim to adhere to Western values and to long for Euro-Atlantic integration. Georgian leaders seem to have made every possible effort to convince a Western audience that their political system is a mess.

That said, accession to both NATO and the EU will remain popular in Georgian society regardless of the escapades of the country’s political class. Russia remains deeply unpopular. And, one day, Georgia may end up with a capable government that not only promises but also implements reforms, thereby improving the country’s relationship with the West. Because Tbilisi conducted some basic reforms in the early 2000s, the obstacles to EU accession talks may not be all that big (so long as the Georgian leadership does not reverse key reforms). Yet, if Tbilisi began these talks, Moscow would then resort to its backup plan – which for non-aligned countries in its neighbourhood means military pressure, if not war.

The Russian military has long had the capabilities to conquer Georgia – having deployed roughly brigade-sized forces in South Ossetia and Abkhazia each, and reinforcements just across the Caucasus ridge – but the operational bases in Crimea are certainly helpful in that regard. Paranoid about Western support for Georgia – real or imagined – Moscow could use Crimea to cut US or European lines of support for Tbilisi.

Even in a crisis short of war, Moscow could declare live-fire exercises south of Crimea down to Turkish territorial waters, effectively demarcating the Black Sea into two zones. Russia has used the safety provisions around such exercises to inhibit or interdict maritime traffic in the Baltic Sea and to cut off Ukrainian ports in the Black Sea since March 2021. Russia can do the same to Georgia – by stopping, searching, and redirecting inbound and outbound naval vessels.

In a further escalation, Moscow could launch an amphibious and airborne assault on Adjara and Samtskhe–Javakheti to control the Georgian-Turkish border. While the border is roughly 200km long, it crosses mountainous terrain with few roads capable of facilitating military supplies. Russia would only need to capture and hold these points. With Georgia’s main manoeuvre forces struggling to keep Russian troops in Abkhazia and South Ossetia at bay, only reserve territorial forces would be available to deal with a Russian incursion from the west. Georgia only began to resurrect its territorial defence forces in 2017, so it is hard to judge their current state. Given Georgia’s capability gaps in coastal and airspace surveillance, Russia could conduct such assaults at the beginning of a transition from a hybrid confrontation to open warfare.

Once a full-blown conflict started, the main aim of Russia’s assets in Crimea would be to effectively play the role of an unsinkable aircraft carrier and missile launch platform. They would provide fire support for Russian ground operations, and would deter NATO allies in the region from providing relief measures or other support to Georgia.

Hybrid incursions into NATO and EU territory

While intimidating and subjugating former Soviet states will remain the primary aim of Russian foreign policy and military thinking, the Kremlin also believes that it is necessary to destabilise the West to keep it at bay. Of course, overt attacks on NATO territory would involve significant risks. Hence, these operations need to be deniable and quickly reversible. Then, if there is a concerted reaction, one can pull back. If there is only confusion and equivocation, one can advance and exploit the situation.

Before Russia’s annexation of Crimea, maritime delimitations in the Black Sea were not fixed. Governments in the region paid little attention to the issue until Romania discovered offshore gas fields in 2012, and Ukraine did so thereafter. Now, delimitation is a controversial matter, as Ukraine does not exercise control over the waters surrounding part of its territory, Crimea. Moscow pushes its territorial claims and underpins them with aggressive military posturing and patrolling, to prevent further exploration or exploitation of these waters. This approach is designed to apply targeted pressure on NATO members without crossing hard borders.

But Russia’s destabilising intelligence and special operations activities are not confined to oil rigs and offshore installations. Russian intelligence operations in Bulgaria are no secret – even if it is difficult to estimate how deeply they have penetrated the government and security apparatus, and how capable they are of paralysing institutions and delaying responses to crises. One case that touches on many of these issues is that involving multiple attempts to murder Bulgarian arms dealer Emilian Gebrev in 2014 and the explosion at a Czech arms depot holding weapons his company owned. Allegedly, these weapons were meant for Ukraine. Russia’s military intelligence directorate, the GRU, tried to prevent the war materiel from reaching the Ukrainian military. Yet, reportedly, the weapons in the Czech storage site, and most others owned by Gebrev’s firm, were not intended for Ukraine; they were headed to US-backed groups in the Middle East. This raises the issue of whether the GRU was sloppy in verifying the intelligence or was intentionally fed bad information.

In 2014 a notorious Bulgarian oligarch wanted to enter the arms trade by taking over or sidelining the competition. Investigative journalists writing for Bulgarian media outlet Bivol suspect that Bulgarian organised crime groups, oligarchs, and intelligence operatives colluded with the GRU to settle a domestic dispute. Some corruption networks run through Bulgarian politicians and private businesses to Russian companies, facilitated by former “colleagues” from the respective KGBs (a name shared by the communist-era Bulgarian and Soviet intelligence services). The EU needs to pay attention to these problems, especially given that the media outlet has been subjected to harassment since publishing articles that describe the toxic convergence of business, organised crime, and intelligence services in Bulgaria.

During the 2015 refugee crisis in Europe, self-declared “border patrol” paramilitary units formed in both Romania and Bulgaria. They received training, and possibly other support, from Russia. Such militias would be ideal proxies for state-sponsored acts of destabilisation and terrorism – as well as, in certain circumstances, the instigation of wider public unrest. Given the age and technical weakness of surveillance infrastructure along the Black Sea coast, it would be easy to reinforce such militias with weapons, advisers, and materiel using small vessels. As Russia is an increasingly repressive authoritarian state, it can also force any Russian company to provide services or allow the use of its facilities for a smuggling and infiltration operation. Some Russian energy companies have large installations and ports along the Bulgarian Black Sea coast that the Kremlin could use for this kind of covert infiltration.

Hybrid paramilitary pressure would be particularly valuable for Russia in coercing Romania or Bulgaria to allow military access to the Western Balkans. A new crisis in the region – triggered by, for example, secessionist forces in Bosnia – would make Russia search for a transit route to Serbia.

In 2015 Bulgaria blocked its airspace to Russian transport aircraft flying to Syria – but, back then, Russia could switch to the route over Iran and Iraq. In flying to Serbia, there is no such alternative route. Stirring up right-wing nationalist actors would create internal pressure to provide Russia with the access it wanted, while an aggressive show of force and manoeuvres in the Black Sea would create external pressure. Russia’s intimidation of NATO members in the Black Sea would most likely avoid overt attacks and occupation, instead forcing them into compliance with its strategic demands.

Turkey as a counterbalance?

Since the 2020 war in Nagorno-Karabakh, some in the West regard Turkey as potentially able to counterbalance Russia’s hegemonic ambitions in the Black Sea. At first glance, Turkey seems to be a natural pick for this role: it is a NATO member, owns the entire southern shore of the Black Sea, has a powerful navy, and is supporting proxies opposed to Russia in the Libyan and Syrian wars, as well as in Azerbaijan. Given that Turkish military advice and weapons deliveries to Azerbaijan were the decisive factors in the country’s recent victory over Armenia in the Nagorno-Karabakh conflict, one might assume that Turkey will replicate this support in other post-Soviet states. But things are not that straightforward.

Since claiming power, President Recep Tayyip Erdogan has remade Turkey in his own image, turning the country away from the West, secularism, and traditional Turkish foreign policy. The 2016 failed coup attempt in Turkey only accelerated these trends. Erdogan’s ‘new Turkey’, embracing the pre-Kemalist Ottoman Empire and longing for a better place under the sun, often mirrors Russia in its foreign policy and normative interests. As with any authoritarian system, the international fallout from keeping power at home – suppressing critics and even harassing the opposition abroad – takes up considerable space in Turkey’s foreign policy and creates a persistent irritant in its relations with the West.

For Ankara, containing Russia is not an end in itself. While Russia is Turkey’s rival in many foreign theatres, it also is a source of stability for Erdogan. Like any other authoritarian ruler, he is preoccupied with domestic threats and opponents. While the West’s human rights and democracy agenda is a latent threat and irritation, Russian policies contain none of these challenges. On the contrary, President Vladimir Putin alerted Erdogan to the 2016 coup attempt, proving that he would not seek or passively tolerate Erdogan’s removal from power. This trust between the two leaders is a strategic factor of its own that one should not underestimate. So far, thanks to this trust, the two leaders have struck deals and drawn red lines in conflicts in which they support opposing sides – and have even deployed their own assets on the ground to back local allies.

That said, Erdogan will not bend to Putin’s interests. Turkey’s exports of weapons to Ukraine, support for Ukraine’s NATO membership, and refusal to recognise Crimea as Russian are clear signs that Ankara is willing to disregard the Kremlin’s sensitivities – and sometimes accept the price of doing so. To preserve Turkey’s independence, Ankara cannot let its relations with Western capitals break down entirely. Hence, since the Biden administration took office, Ankara has seen support for Kyiv as a means of generating political capital in Washington.

Nevertheless, defence-industrial relations with Ukraine are important for Turkey’s own agenda, irrespective of the West and Russia. Since coming to power in 2002, Erdogan has sought to build up a domestic defence industry that is as independent of the West as possible. Erdogan understood that overreliance on the US and Europe for arms imports would make him vulnerable when pursuing his new foreign policy in Africa and the Middle East, which is often at odds with those of Western countries. This prediction came true when: the US froze deliveries of the F-35 fighter in response to Turkey’s purchase of the S-400 air-defence system; many European countries and Canada stopped supplies of arms and military components to Turkey following Turkish military action against the Kurds in northern Syria; and during the Nagorno-Karabakh conflict in 2020. Turkey started several ambitious defence-industrial projects: the Altay main battle tank, the TF-X stealth fighter, an extended-range SOM cruise missile, the Istanbul-class frigate, and the Hürjet light attack aircraft. But most of these projects have stalled because key components – jet engines, tank engines, transmission gears, electro-optical equipment, special armour materiel, and so on – were to be imported from Western companies that no longer work with Turkey due to political strains.

Enter Ukraine. Once a core pillar of the Soviet Union’s military-industrial complex, the country produced a wide variety of weapons systems – from tanks to warships, to intercontinental ballistic missiles – and is now desperately looking for investment to revive a defence sector that it needs in a time of war. Ukraine had long tried to access other defence markets and seek cooperation for development projects. But Europe’s defence market remains closed, because its domestic champions fear competition from their Ukrainian counterparts (which produce some of the same products). Before 2014, Ukraine hoped that cooperation with China would help develop the defence sector. For example, China’s technology to build carrier-capable fighters and operate an aircraft carrier came from Ukraine, as the Soviet enterprises to develop these capabilities were situated in Ukraine. However, Kyiv ended its cooperation with Beijing after 2014, in response to US pressure.

Ukraine’s military cooperation with Turkey will hardly cause the same concerns in Washington as did Ukrainian exports to China or Iran – nor will Turkey’s purchases of weapons or subcomponents from Ukraine rather than Russia. Hence, the defence-industrial relationship between Kyiv and Ankara is much less ‘geopolitical’ than most observers might think or hope. The relationship will grow purely for financial, industrial, and technological reasons, probably regardless of what both countries do politically. Ankara will certainly not sacrifice this relationship for fair weather with Moscow, as it serves too many long-term Turkish interests. Equally, Ankara will not necessarily jump into a crisis on Kyiv’s behalf, because doing so would create a set of risks and repercussions it wants to avoid.

So, ultimately, it is hard to predict where Turkey will stand in each of the scenarios mentioned above. Much will depend on the broader circumstances and the short-term bargains to be gained or lost. In Washington, the call for a genuine outreach to Ankara and the launch of a privileged strategic dialogue is understandable. But, from a European perspective, this approach is tricky to implement. Erdogan will want to negotiate on not only foreign policy and economics but also issues outside Europe’s comfort zone. When Erdogan infringes on the rights of his perceived domestic opponents – such as journalists, dissidents, or civil society organisations – and those who have dual citizenship, a bargain between Turkey and Europe could hit the rocks. Any demand for European civil society organisations or courts to behave in the way he wants, and to pressure European governments to achieve this, will have similar results.

Therefore, rapprochement between Turkey and Europe will need support from Washington. Economic, societal, and other ties between the US and Turkey are relatively insignificant, and hence involve far fewer irritations and dead ends than European-Turkish ones. And, finally, Ankara wants reassurances on security from Washington. Europe can and should provide economic incentives for Turkey to cooperate, so long as these incentives remain within the limits of what Europe can realistically tolerate.

Europe and the US should try to engage with Turkey in everything they do in the Black Sea, to avoid aggravating Ankara’s suspicion of the West and to maximise Turkish participation in their initiatives there. Even if the Turkish armed forces were only a training partner for other Black Sea militaries, they would bring much to the table – particularly in the fields of anti-submarine warfare, air-maritime coordination, and electronic warfare. But the US and Europe should not make everything they do in the region dependent on Turkish participation and goodwill. Ankara’s main interest is in elevating its own position vis-à-vis both Moscow and Washington. And it will use any dependency it can to increase its leverage over either party.

As a consequence, Turkey is neither the problem nor the solution in the Black Sea region. Ankara does not push a revisionist or confrontational agenda there as it does in the eastern Mediterranean. But its willingness to counteract Russian moves has limits. Europe should encourage and even reward Turkish efforts to increase Black Sea security if they happen, but should not take them for granted. The default Turkish position on Russia’s territorial disputes with other Black Sea states is one of ambivalent neutrality.

Vulnerabilities and strengths of the Black Sea countries

The vulnerabilities of Bulgaria, Georgia, Romania, and Ukraine are similar in nature, albeit different in scale. Given that only two of these countries are members of NATO and the EU, they will need to address their vulnerabilities in different ways.

Cross-domain defence

The first problem is situational awareness. Western countries need to continually monitor the Russian Black Sea Fleet, as a recent increase in its activity and logistical preparation indicate that it is planning something. The Bulgarian, Ukrainian, and Romanian navies have signals-intelligence units, but it is hard to assess their ability to intercept and interpret Russian naval communications – especially given that the Russian armed forces have completely overhauled their command and control networks since 2008. It is no secret that Ukraine has to rely on US intelligence exchanges to track Russia’s military movements beyond its borders. Other littoral countries operate similarly old intelligence gathering equipment and, with the exception of Romania, have not yet undergone a modernisation effort. Although the relevant capabilities are classified, tracing and deciphering Russia’s communications appear to be beyond the capabilities of other Black Sea states. Turkey may be the only exception in having the capability to at least trace Russian signals – but there is little evidence that it shares this sort of information.

Furthermore, Russia seeks to intercept and interpret the naval communications of these states. Beyond the technical intelligence capabilities discussed above, Russia heavily relies on human intelligence to penetrate foreign bureaucratic, political, security, and economic structures – with its agents not only providing information on the country’s plans and intentions but also, if needed, obstructing responses to Russian action. These well-financed and comprehensive efforts at subversion target unreformed intelligence services, domestic corruption networks, suboptimal systems for protecting the rule of law, and captured state institutions.

Public distrust of Moscow sometimes helps limit the scope of these Russian operations, but it cannot compensate for institutional weaknesses that an adversary can exploit (which vary from country to country). While the strategic significance of the fight against corruption, rule of law reforms, and intelligence sector reforms have been discussed in previous ECFR papers, one should remember that shortcomings in these areas have military consequences as well – especially if left unaddressed. Likewise, intelligence reform and foreign assistance to boost the capabilities of domestic intelligence services – particularly in Ukraine, Georgia, and Moldova – are not only a measure to fight corruption and protect human rights; they are also important to improve the conventional military security of those states.

Coastal defences and naval power

Coastal defence and coastal surveillance are also key issues. All Black Sea countries other than Turkey have Soviet-designed coastal surveillance and defence structures. This means that Russia knows the exact technical specifications of their radar and communications systems – and, accordingly, how to locate and jam them (although it would know the location of stationary installations in any case). Given that the threat from Russia is creeping from the subversive to the openly military domain, Black Sea states need to modernise – and develop common operational concepts for – their paramilitary coast guards, navies, and coastal defence forces.

These defensive weaknesses are most apparent in Bulgaria. The country’s navy and coastguard predominantly use cold war-era communications and surveillance infrastructure. Like most former members of the Warsaw Pact, Bulgaria reorientated its armed forces around expeditionary warfare and the deployment of soldiers to international stabilisation missions after joining NATO, causing the navy to slip down the priority list. For deployments to Afghanistan, there was no need for a navy. The few funds available went into modernising the land forces, particularly those that deployed abroad. There were isolated attempts at modernisation in the purchase of three used 1970s-era Wielingen-class frigates from Belgium. And Bulgaria is engaged in negotiations about the possible purchase of Ula-class submarines from Norway. The problem is that these platforms would be the only Western-made items in a navy that still relies on Soviet equipment for communications, electronic warfare, and logistics. A deeper modernisation and renewal of the Bulgarian Navy’s coastal defences would require more funding than is currently available.

Georgia had difficulties building up a navy after independence – and what little it had was destroyed by Russia in 2008. In some ways, that was a blessing as well as a curse: it prompted Georgia to build up an effective naval border guard (instead of a navy) that was modelled on the US Coast Guard and came with advice and training from the US thereafter. The naval border guard has land-based installations and a flotilla of small craft to surveil and otherwise monitor Georgia’s coastline and exclusive economic zone. The force can act in all sorts of hybrid scenarios against state-sponsored ‘private’ entities. But Georgia lacks coastal defence capabilities of any kind. Given its exposure to a land-based Russian attack from its breakaway regions, the country has priorities other than building up an expensive navy. But this means that Georgia will not be able to impose operational risks or costs on Russia for the sort of naval incursion described above.

Ukraine’s navy and sea guard took a similar hit with Russia’s 2014 invasion and annexation of Crimea, the location of most Ukrainian naval installations (such as yards, logistic centres, bases, academies, and training sites). Rebuilding infrastructure in Odessa and Mariupol was the immediate priority for Kyiv. And, much like their comrades on land, Ukraine’s navy and sea guard are constantly occupied with a hybrid war – fighting saboteurs, disruptive foreign intelligence officers, infiltrators, and those engaged in illegal fishing, especially in the Sea of Azov. Ukraine’s current set of primarily small and fast patrol craft is well suited to this task.

Whenever they venture beyond Ukraine’s coastal waters, these naval vessels are harassed by Russia’s Black Sea Fleet, which significantly outnumbers and outguns them. In 2014 Russia occupied Ukrainian offshore facilities not only in Crimean waters but also in the Ukrainian exclusive economic zone around Odessa. Since then, it has used them as heavily guarded outposts. Ukrainian small craft approaching them are driven off by force. Ukraine’s small craft are incapable of posing a significant threat to Russian amphibious operations in Ukrainian territory. They cannot contest the closure of international waters by the Russian Navy, because they would be easily overwhelmed and boarded if they left protected coastal waters – as happened in the Sea of Azov in 2018.

Ukraine has started to modernise its coastal defences and coastal surveillance systems, including its naval signals-intelligence equipment. For instance, the country has introduced the Neptune coastal defence missile system. Kyiv has made a lot of ambitious declarations about upgrading its coastal defences – such as President Volodymyr Zelensky’s June 2021 announcement that Ukraine will build a powerful navy – but it is hard to tell how quickly it is implementing these plans, if at all. Even if the first Neptune batteries come online in 2021, their operational effectiveness will depend on Ukraine’s ability to detect, locate, and classify Russian naval vessels far out at sea. Nevertheless, the missile expands the grey zone in which Ukraine can increase the costs of Russia’s naval bullying.

A significant boost to Ukraine’s maritime capabilities could come from the naval cooperation agreement it signed with the United Kingdom on 23 June 2021. The first stage of the arrangement will see the Royal Navy support the training of Ukrainian Navy personnel and units. The UK will assist with the modernisation of Ukraine’s naval bases and logistics systems, so that they are capable of operating and maintaining modern vessels. The UK will also provide two mine-countermeasures ships and, if the first stage of naval modernisation is completed, help Ukraine construct new missile craft and frigates. The agreement includes plans to refurbish existing platforms with new weapons, sensors, and command and control equipment.

When completed, this would indeed enable the Ukrainian Navy to introduce considerable risk into Russian offensive operations against it, and to challenge the Russian Navy’s restrictions on Ukrainian freedom of navigation. However, one can only hope that Ukraine has the budget to fulfil these aspirations. The agreement attaches no timeline to the projects, and the UK has not involved other countries in the effort, intending to manage on its own. This approach may soon collide with the reality of budgets affected by both Brexit and covid-19. Similarly, Ukraine has also committed to building frigates with Turkey – and, again, one may wonder how all the projects will be budgeted.

Romania centred its military reforms on the demands of expeditionary warfare but, in comparison to Bulgaria, changed its approach more quickly after Russia’s invasion of Crimea. Like its neighbours, Romania acquired the bulk of its military equipment – onshore as well as naval vessels – during the cold war. And while the country built its sensors and weapons at home, they were of Soviet origin or compatible with Soviet designs because, back then, the Romanian Navy operated within the Warsaw Pact. Two 1970s-era British Type 22 frigates are the exceptions to this.

Like other states in the region, Romania plans to modernise its naval and coastal defence infrastructure – the most visible indications of which are its purchase of the Naval Strike Missile for coastal defence forces and its contract to build four new corvettes. Romania increased its defence budget from $2.78 billion in 2016 to $5.21 billion in 2020, allowing it to engage in a broader force modernisation than that in neighbouring countries.

However, the biggest game-changer for Romania could be the creation of the NATO Multinational Corps Southeast, headquartered in Cincu. The new operational command mirrors NATO Multinational Corps Northeast – which is headquartered in Szczecin, and which would lead allied joint operations in the Baltics in case of war – and should provide not only a wartime joint operational command but also a staff that processes and evaluates intelligence and force planning in peacetime. Such a high command, if fully operational and trained in peacetime, is an effective way to increase interoperability between nations and different service branches in a wide variety of crisis contingencies. However, for now, Multinational Corps Southeast is a rather Romanian endeavour, having received few contributions and little financing from the rest of the alliance.

Air power

Surveilling and defending the coast and littoral waters against hybrid and conventional incursions is one issue; surveilling and defending one’s airspace is quite another. There are plenty of contingencies to prepare for – ranging from infiltration by reconnaissance teams and saboteurs who parachute from civilian aircraft into Black Sea countries, to airspace violations by conventional aircraft as a means of intimidation, to wartime attacks by aircraft and missiles from Russian forces based in Crimea. And, again, Black Sea countries mostly rely on Soviet-era equipment and infrastructure – including airspace-surveillance radars and networks, fighters, and ground-based air defences and their corresponding networks – to cope with these threats. Therefore, Russia knows how to jam their radars and use countermeasures against their missiles. Modernising this infrastructure would take a lot of time and money. It would mean not just purchasing a few systems but changing infrastructure, logistics, and procedures from the ground up.

Georgia had invested in the modernisation of its airspace-surveillance and early-warning hardware before the 2008 war – and had some surprise successes, such as when it shot down a Russian Tu-22M bomber with a Buk-M1 – but, ultimately, the conflict destroyed what was left of these capabilities. Georgia disbanded the air force after the war (while retaining an air wing of the ground forces) but re-established it in 2016. The country also received some new equipment – particularly airspace-surveillance radars and short-range, point-defence surface-to-air missiles – from France. However, longer-range missiles suitable for area defence were too expensive for Georgia, even if France was willing to sell them.

In a crisis short of all-out war, Georgia does not have fixed-wing aircraft to patrol its airspace and enforce air-traffic rules. This could be a problem if, for example, the Nagorno-Karabakh conflict prompted Russia to provide reinforcements to Armenia by violating Georgian airspace, and Turkey protested against the move. Georgia could easily be drawn into a conflict it did not intend to take part in. Russia could use unpatrolled Georgian airspace for targeted provocations, but it would be a drastic measure for Georgia to shoot down an intruding aircraft in a tense situation using one of its surface-to-air missiles. It would also be a politically unviable option if the other side was waiting for a pretext to escalate. But building up independent airspace policing capabilities is expensive for a small country such as Georgia, especially if it has to simultaneously strengthen the capabilities of its territorial defence forces and ground forces. Compared to airspace patrol, ground capabilities are more important in resisting a full-blown invasion by Russia.

Ukraine has also paid relatively little attention to air and air-defence forces in its reconstruction of the armed forces. After the country’s air force performed patrolling and transport duties in the initial phase of the Donbas war, Russia’s July 2014 decision to deploy a wide array of surface-to-air missiles in Donbas put an end to these operations. By then, Ukraine’s air force and army aviation force had lost one Su-24, six Su-25s, two MiG-29s, one An-26, one An-30, one Il-76, five Mi-8/17s, and five Mi-24s – a trend that gained international attention when Russian forces shot down civilian airliner MH-17 in July 2014.

Since then, Kyiv has been under the constant threat that Russia will escalate by starting to use its air force over Donbas or other parts of Ukraine. Such air operations do not necessarily have to happen in the context of total war between the two countries. The Kremlin may consider launching targeted air operations or incursions so as to provoke Ukraine or destabilise its political system. As Ukraine relies on Soviet-era technology for airspace surveillance (through ground-based radars and air-to-ground communications), ground-based air defence, and interceptors, the Russian Air Force can not only read the country’s communications but replicate the Ukrainian force structure in Siberia and rehearse air operations in quite realistic conditions beforehand – thereby reducing the risks it faces in conducting such operations.

Ukraine has drawn up plans to modernise its air force from the ground up in the past five years, but it has not begun to implement them. For example, Ukraine declared that it would replace its ageing Soviet-era fighters with modern US or European ones. But, after France offered to sell Ukraine Rafale fighters, the high costs of acquiring and maintaining Western planes became apparent (even if, compared to the Eurofighter and the F-35, the Rafale is relatively easy to maintain, as it is designed to operate in challenging conditions in Africa). And while fighters are the most prestigious part of air force modernisation, this process also requires the corresponding Westernisation of procedures, training, command and control, airspace surveillance, electronic intelligence installations, munitions, and logistical protocols.

Bulgaria has begun the kind of modernisation effort that Ukraine desires. After Bulgaria joined NATO, the country’s air force fell off its list of priorities for modernisation because it would not be suitable for international missions. Still, in 2019, Bulgaria purchased eight F-16 fighter jets from the US to modernise its air force. However, as discussed above, Westernising the air force requires more than the acquisition of fighters. Many within the Bulgarian armed forces hope that the F-16s purchase will spark a wider modernisation effort – one that will also touch upon other services to promote inter-service operability (in this particular case, allowing the navy to exchange data with aircraft). Others fear that the government will end these efforts once it realises the costs of modernisation.

The story has been roughly the same in Romania, albeit with the Romanian strategic consensus on the aim and role of the armed forces helping considerably. Unlike in Bulgaria, there are no major pro-Russian domestic political forces in Romania. Hence, there is little hesitation in calling out the Russian threats even in official documents, and adjusting defence policy towards deterrence and defence. Before 2014 Romania, like most other NATO members, focused on expeditionary warfare: the only new air assets Romania purchased between joining NATO and 2014 were transport aircraft, as the country saw the air force’s primary job as being to transport supplies and personnel to distant conflict theatres. Then, Russia’s invasion of Crimea left Romania facing one of the most militarised parts of Europe overnight, forcing its planners to readjust. The most visible part of Romania’s modernisation effort is its purchase of 17 F-16s from Portugal since 2015 (more will follow). But Romania is also investing in airspace-surveillance radars, command and control infrastructure, munitions, and layered integrated air defence – including seven batteries of Patriot surface-to-air missiles, the newest batches of which the country will purchase from 2022 onwards – and in the thoroughgoing modernisation of infrastructure, training, and operational schemes. As discussed above, the drastic increase in Romania’s defence budget after 2016 allows for the most comprehensive modernisation effort in the Black Sea region. Nevertheless, the country will only complete this process in the 2030s, thanks to the sheer number of procurement programmes and procedures it needs to implement.

Policy recommendations for Europe and NATO

None of the Black Sea countries can handle the Russian challenge on its own. They all need Western support to increase their resilience and defence capacity, and to handle Russia’s provocations or even wartime escalation. This support – including forward-deployed forces, if possible – should enable these states not to win a conventional war (let alone one involving nuclear weapons) but to impose significant costs on Russian military aggression. To significantly lower Moscow’s chances of success and increase the risk that it will lose troops and materiel, the Black Sea states need to: reduce Russian intelligence penetration of their institutions; establish secure military and civilian command and control networks; operate military systems that Russia does not know well and whose signals it cannot intercept and decrypt; adopt Western military procedures and tactics, which Russian planners will find harder to counter than Soviet doctrines; and, finally, train and equip their armed forces to a level that enables them to fully participate in combined manoeuvre operations with allies. As discussed, the likelihood that the Kremlin will pick a fight decreases with the predictability of the outcome.

Increased situational awareness and communications security

The first issue is intelligence on Russia’s Black Sea Fleet and military forces in Crimea. For the time being, the US provides much of this intelligence – using satellites, P-8 Poseidons, and unmanned aerial vehicles to monitor the fleet in Sevastopol and its electronic emissions (from the activation of radar antennas and signalling commands). The US then passes this information to its allies and partners. America’s maritime surveillance capability is certainly the most advanced in the world, but it is also a scarce resource – because it is tasked with monitoring the Chinese People’s Liberation Army Navy as it expands its activities globally. While Black Sea countries should routinely improve their land-based intelligence gathering capabilities, the deployment of more European unmanned aerial vehicles and other intelligence gathering aircraft in their region would quickly augment their capabilities. Unfortunately, recent acquisition programmes in major European countries face delays.

Maritime patrol aircraft provide a fast and efficient way to react to and gather information on incidents at sea. The sudden appearance of Turkish maritime patrol aircraft has made Russian vessels back off from Ukrainian ships in the Black Sea. If EU member states operated maritime patrol and reconnaissance aircraft from Romanian and Bulgarian bases, this could increase the frequency of such flights.

And it bears repeating that the intelligence gathering assets embedded in armed forces cannot be effective without support from functioning, capable, and integrated civilian intelligence, counter-intelligence, law enforcement, and anti-corruption institutions. While it is relatively easy to assist Black Sea countries using NATO’s technical intelligence assets, it will be much harder to compensate for the fact that the EU’s previous enlargement rounds and current neighbourhood policy did not prioritise intelligence reform (an area in which member states themselves have many shortcomings).

Multinational surface forces

In a crisis, surface ships are important to signal resolve and solidarity. In previous crises, such as the 2008 Russia-Georgia conflict and the 2021 war scare in Ukraine, the US tried to move naval ships through the Bosporus in response. However, transit through the Bosporus is slow – as the Montreux Convention demands notification of such moves eight days in advance – and prompts Russia to pressure Turkey to block it. But, if NATO members deploy warships in the Black Sea on a permanent rotational basis, they can react much more quickly. Like the Enhanced Forward Presence in the Baltic countries, the presence of ships of multiple allied countries would complicate Russia’s calculations by increasing the risk that military aggression against Black Sea states would result in escalation. This would also take some of the pressure off these states to decide how to react alone.

Of course, the Montreux Convention places limitations on the international naval presence in the Black Sea. European countries would have to deploy vessels – on a rotational basis – to the sea, where the aggregated displacement of all foreign navies’ ships should not exceed 30,000 tonnes. These operations would need to involve multiple nations, as the convention forbids any one nation from using up the limit on its own. But none of these issues should be a problem for a multinational alliance. A modern frigate has a displacement of around 5,000 tonnes and an anti-submarine-warfare corvette roughly half that, while supply ships and minor vessels such as minehunters are excluded from the tonnage regime. It would be possible to assemble an allied task force that comprised two or three frigates and some sub-chasers and auxiliaries, and that regularly rotated individual ships. Such a task force could react flexibly to any incident in the Black Sea and thereby strengthen European political positions in the region.

In 2016 NATO tried to set up such a taskforce, one comprised exclusively of ships from its members Bulgaria, Romania, and Turkey. But the idea quickly fell apart: because only the Turkish navy could provide a large number of surface vessels, Bulgaria feared that Turkey would dominate the taskforce. While all NATO’s members and partners could contribute to a surface force provided and led by non-littoral states, an approach that relied on external actors would help defuse these kinds of political rivalries between Black Sea countries.

Freedom of navigation patrols

Freedom of navigation patrols, such as those Western states conduct in the South China Sea, are another means to emphasise that Europe rejects Russia’s claims to Crimea and arbitrary closures of sea routes. However, European states would need to combine these patrols with an effective communications strategy: as such operations are only statements made by ships, the message needs to be clear from the start.

In June 2021, the Royal Navy destroyer HMS Defender entered a Russia-declared restricted zone south of Crimea on its way from Odessa to Georgia, aiming to emphasise the British government’s dismay at Moscow’s unilateral actions. This operation was fine in principle, but the UK did not tell anyone what the ship was doing or where it was travelling to beforehand, giving the Russian press a chance to publish exaggerated stories about the “incursion” first and thereby shape the narrative around the incident. The UK Ministry of Defence only issued a short statement denying Russian claims hours after the operation, despite an onboard reporter recording a tense situation with Russian vessels trying to drive them off. The operation not only failed to communicate a clear message about the lack of legitimacy in Russia’s claim to Crimea but also created confusion that helped emphasise Moscow’s main message: challenging Russian conquests means trouble. Prior consultation with allies, mutual support, and clear messaging would have prevented this. The Royal Dutch Navy did a much better job of this recently – after one of its ships, the HNLMS Evertsen, was harassed by Russian aircraft in international waters near the Kerch Strait.

Nevertheless, the Russian armed forces are increasingly aggressive in harassing NATO ships in international waters in both the Black Sea and the eastern Mediterranean. Moscow wants to push the boundaries of no-go zones for NATO forces, in violation of international maritime law. Russia insists on its own right to freedom of navigation when moving warships through the Belt and Sound or the Channel, or when its aircraft carriers want to refuel in Spanish ports or Russian Navy ships seek to wait out a storm in protected British waters. As Western countries want to uphold freedom of navigation, they refuse to impose restrictions in kind. But they need to push back assertively against Russian provocations and demonstrate a willingness to use force.

Military capacity building

Moreover, Black Sea states need capacity building programmes to help improve their coastal- and air-defence capabilities. As discussed above, the costs of military modernisation are staggering. The countries of the Eastern Partnership and littoral states that are members of NATO and the EU have insufficient financial resources to do this on their own – confronted as they are with the Russian threat emerging from across the sea. And the most vulnerable Black Sea countries – particularly Georgia and Ukraine – have higher priorities than coastal and air defence. Europe in particular should provide them with specific military assistance, in the form of loans and second-hand equipment, to ease the financial burden of modernisation. For the time being, only US foreign military aid programmes are available to allied and associated countries in the region. Western training and advice would also be beneficial, as the interoperability of Ukrainian, Georgian, and NATO forces is key to coordinating responses to crises. Even if Georgia and Ukraine are not part of NATO, Western states should signal to Moscow that the two countries will not inevitably be alone in a confrontation with it.

NATO also needs to consider extending air policing missions to non-member countries. This type of mission is usually known for guarding the airspace of the three Baltic countries, each of which is too small to operate its own fighter force. But there are other examples of such missions: Italy conducts air patrols in Slovenia. And, since 2014, NATO’s Enhanced Air Patrolling has helped fill gaps in this area in Romania. The mission also increases the interoperability of the NATO air forces operating there, and helps the Romanian Air Force with its modernisation effort by providing training and manoeuvre exercises. So far, such operations are reserved for NATO member states. But, given the volatile security environment in the Southern Caucasus, it would be dangerous to leave Georgian airspace unpoliced. Due to Georgia’s current political situation, such a service would have to be bound by strict conditions.

It is also important for NATO to provide assistance to Romania’s and Bulgaria’s efforts to modernise their ports, maritime surveillance infrastructure (including radars and sea-floor sonars), airbases, air-surveillance radars, and maritime and aerial command and control infrastructure. This is because, in times of crisis, allied reinforcements will have to use the infrastructure. Expanding the role of Multinational Corps Southeast and increasing its funding could support the modernisation of Romanian and Bulgarian command and control structures. In the Baltic Sea, NATO has considerable strategic depth as it is able to use Danish and German ports and airbases to bring in reinforcements or conduct other missions. Yet, in the Black Sea, the alliance lacks this depth and depends on facilities there.

Multinational Corps Southeast

Multinational Corps Southeast should receive more attention from European countries. It serves as a common command structure to conduct operations during crises, plan and prepare for them in peacetime, transform intelligence on Russian preparations into allied force planning, and liaise with host countries’ authorities. But, to play this role effectively, the corps will require more NATO budgetary support for the modernisation of local command and control infrastructure. Like any military command, Multinational Corps Southeast needs training, exercises, and other preparation to carry out its wartime functions. Given that the corps played an important role in the US-led Defender 21 exercise, one can only hope that more exercises rehearsing both deployments and combined operations will follow in the coming years (Russia’s protests against Defender 21 reflect the exercise’s strategic significance).

The NATO-Russia Founding Act restricts the size of permanently deployed combat formations to former Warsaw Pact states. However, there is nothing in the act to prevent the deployment of force enablers and combat support formations to facilitate the corps’ role in manoeuvres, training, intelligence gathering, and planning. And this would help facilitate local military modernisation efforts. The US had started this effort in the 2000s, with US European Command’s Black Sea Area Support Group modernising training sites and building up facilities able to host up to a brigade in Romania and Bulgaria each. However, the main purpose of the erstwhile initiative was to train local ground forces for expeditionary missions in Afghanistan and Iraq, not a joint air-sea-land battle against a possible Russian threat.

From a European perspective, it is striking that the US has such a pivotal role in most Western military efforts in the Black Sea region. The US organises more exercises there than any other nation, deploys troops for training on a rotational basis to Romania and Bulgaria, has a base in Romania, provides the most military intelligence to Black Sea states, and contributes many officers and assets to joint structures. While European leaders often like to declare that they should take greater responsibility for their own security, a glance at their activities in the field indicates that they have not done so.

This does not mean that there is no demand for European action. For example, Romania once intended to join Germany’s framework nation initiative (under which a Romanian brigade would have been subordinated to a German division to train and exercise with it). But it soon became apparent the initiative would be hampered by the geographical distance between the countries and the Bundeswehr’s practical preparation for Article 5 operations focused on its immediate neighbourhood and the Baltic Sea. Some Bulgarian policymakers have noted that, given the charged European debate on geopolitics, many force-modernisation efforts would be easier to sell if they were led by Europeans. The same applies to foreign military aid, which is only available from the US.

Military mobility

Strategic mobility is also an issue. In a crisis, the US and European countries need to be able to deploy deterrent forces quickly. This effort is hampered not only by the low readiness of most European armed forces but also by infrastructural challenges. Heavy armour units need to be transported by train. However, it is time-consuming to conduct such deployments from Germany through Poland, Slovakia, Hungary, Romania, and Bulgaria. This is partly because, in most central and eastern European countries, east-west rail connections receive much more attention – and investment in renovation – than north-south ones due to their higher commercial value. Transit through the Mediterranean and Aegean seas, followed by shipping from Greece into Bulgaria, would be an alternative route. This route has seen increasing commercial use in recent years but has not yet been tested for the deployment of troops.

The EU’s structural funds are a crucial resource for modernising infrastructure such as roads, railways, bridges, and ports. The bloc has already taken the important step of incorporating military standards into infrastructure-modernisation projects. Yet other important types of infrastructure – such as military airfields, ports, and bases – are not covered by current EU funds but are still critical to providing reinforcements to Black Sea countries. To host allied aircraft in case of a crisis, Romania and Bulgaria need to upgrade their airbases to standards at which they can operate and maintain modern Western fighter aircraft while hosting potentially expanded units of their own air forces. In the 1950s, Germany and Italy provided airbases to the US Air Force, which then expanded them to host their air forces. But, given the limitations imposed by the NATO-Russia Founding Act, there is no way to repeat this in the Black Sea. As NATO has limited funds, the EU should respond to these challenges by creating a Permanent Structured Cooperation project for military infrastructure. Meanwhile, Washington has acknowledged the problem: in 2021 the US provided $152m to modernise and expand Campia Turzii airbase in Romania, to host allied forces in times of crisis or war.

Membership of the EU and NATO provides Romania and Bulgaria with some tools to cope with the challenges ahead. In contrast, Georgia and Ukraine are confronted with similar challenges and have no such advantage. These two countries can never be sure how much support they will receive from the West in a crisis or, accordingly, how much they will need interoperability with Western forces. Of course, the more interoperable their militaries are, the more the West can provide such support – but there will always be a risk in investing in this. While Georgia has invested more than Ukraine in interoperability, the former’s domestic political crisis makes the US and most European countries somewhat hesitant to deepen their engagement with it.

Nonetheless, this risk will always be there. Building up interoperability between armed forces takes a considerable amount of time, while day-to-day government politics changes quickly – one day for the better, another for the worse. But, in the event of a crisis, only a decent level of interoperability would enable the West to react – or, at least, credibly threaten Moscow with a reaction – by increasing the uncertainty around, and unpredictability of, the Kremlin’s military efforts.

Time and again, many European countries confuse the need to support their neighbours – even militarily, to increase their interoperability – with the issue of accession to NATO or the EU. During the cold war, the UK and the US maintained ties to the Austrian and Swedish armed forces, thereby ensuring a minimal degree of interoperability in logistics, equipment, and officer training, and preparing for various scenarios of crisis and war through informal consultations (which the Swedes took far more seriously than the Austrians did). None of this required Austria or Sweden to join NATO. Nor did it signal that the Western alliance would unconditionally defend them in the case of war. The cooperation stemmed from the realisation in Washington and London that one’s own security, and the security and stability of Europe, required engagement beyond the formal borders of the alliance.

European countries need to approach the Eastern Partnership’s Association Trio – Georgia, Moldova, and Ukraine – with the same open mind. Membership of NATO and the EU is only an issue that needs to be decided upon after these states meet all the necessary requirements. But they will not be able to do so quickly. In the meantime, there are many daunting security issues that Eastern Partnership states must address if they are to survive as independent nations.

About the author

Gustav Gressel is a senior policy fellow with the Wider Europe programme at the European Council on Foreign Relations’ Berlin office. His topics of focus include Russia, eastern Europe, and defence policy. Before joining ECFR, Gressel worked as a desk officer for international security policy and strategy in the Bureau for Security Policy of the Austrian Ministry of Defence from 2006 to 2014, and as a research fellow of the Commissioner for Strategic Studies with the Austrian Ministry of Defence from 2003 to 2006. He was also a research fellow with the International Institute for Liberal Politics in Vienna. Before his academic career, he served five years in the Austrian Armed Forces. Gressel holds a PhD in Strategic Studies from the Faculty of Military Sciences at the National University of Public Service, Budapest, and a master’s degree in political science from Salzburg University. He is the author of numerous publications on security policy and strategic affairs, and is a frequent commentator on international affairs.


This paper has a long prehistory, as Black Sea security issues have been on the author’s radar for a while. However, as other events interfered with writing, and the pandemic interrupted planned rounds of interviews in the Black Sea states, the project took some time to mature. Much like fine wine, it has hopefully not lost its flavour over time.

During all this time, Nicu Popescu and Vessela Tcherneva supported the author in his efforts to write the paper, for which they deserve special thanks. The paper would not have been possible without Tania Lessenska and Daniel Stefanov providing contacts and excellent interview partners in the region. The author would like to sincerely thank them both for all the time and effort they put in. Last but not least, Chris Raggett deserves thanks for the smooth, fast, and professional editing of the paper, as does Marlene Riedel for turning the author’s unreadable scribbles into attractive graphics.

The European Council on Foreign Relations does not take collective positions. ECFR publications only represent the views of their individual authors.

Subscribe to our weekly newsletter

We will store your email address and gather analytics on how you interact with our mailings. You can unsubscribe or opt-out at any time. Find out more in our privacy notice.