Combat lessons: What Europeans should learn from Ukraine

Ukrainians have, against all odds, kept Russia’s military might at bay for over four years. In so doing they have demonstrated the arrival of a new era of warfare in which military power is no longer denominated in numbers of platforms (tanks, ships, combat aircraft), but rather by drones, robots, missiles and information technology. Now these are the things that matter.

Europeans insist they have taken this lesson to heart. Politicians, militaries, industry and even the European Commission have been quick to proclaim that air and missile defence, long-range missiles and autonomous systems are the new top priorities for investment. “Transformation” is the watch-word. Industry is learning from the pioneers of this new way of war and moving quickly to invest in Ukraine while building up tech and production partnerships—with an eye on the future of defence.

But buying new kit only scratches the surface of how Europeans can deter Russia in the event that America, under President Donald Trump, rolls back its military protection still further. Europeans need to act on three other, more uncomfortable, lessons learnt from the war in Ukraine.

Lesson one: Declutter the military inventory

Procurement needs redirecting. The need is not just to buy new stuff, but to give up old stuff as well. The easy consensus about “more money for defence” obscures this (though, to judge by the delay in publication of Britain’s Defence Investment Plan, the Treasury has fought a rear-guard action against the defence ministry’s demands for more money). It is natural that, across Europe, both industry and top brass should be deeply attached to the old platform programmes. Industry because ponderous, multi-year procurements of big-ticket items like submarines and aircraft are where it makes its money; top brass because it is around such equipment that their services (and careers) are structured.

Tradition, central to the military ethos, plays a big part as well. Poland’s cavalry regiments (to be equipped with 180 new Korean tanks) are the heirs of King Jan Sobieski’s hussars, routing the Turks at the gates of Vienna. Britain’s redundant aircraft carriers salve the national sense of declining global power. But failing to declutter the military inventory wastes not just money, but also manpower, management attention and opportunities for non-traditional suppliers (often small hi-tech companies) to inject fresh thinking.

Lesson two: Military strategy needs to adapt

In Europe, the burden of legacy equipment and the associated cold-war military thinking, based on the threat posed by massed Soviet tank armies, obstructs a clear-eyed reassessment of future defence needs. As a result, Europeans have struggled to determine how they can fight to defend themselves against a revanchist Russia without America.

The US model of multi-domain, manoeuvre warfare was all very well while the Americans were running NATO and providing the bulk of its forces and key systems. But now NATO is disintegrating; left to their own devices, Europeans are in no position to practise such sweeping, all-arms warfare. Nor, critically, do they need to. The Ukrainians learned this for themselves when, under NATO instruction, their old-style armoured counter-offensive in 2023 failed.

There has, since then, been no Ukrainian clamour for more tanks from their allies (or even for more combat aircraft), with the counter-offensive demonstrating the overwhelming advantage that defence now enjoys in this new era of warfare. The spectacle of the remnants of the Russian Black Sea fleet holed up in harbour, and the Russian air force skulking back in Russian airspace, underlines how much has changed since the full-scale invasion in 2022.

Europeans need to conduct a root-and-branch rethink of European military strategy and doctrine. They should move away from concepts of manoeuvre and reinforcement towards forward defence

Europeans need to conduct a root-and-branch rethink of European military strategy and doctrine. They should move away from concepts of manoeuvre and reinforcement—complex air and land battles across the North European Plain—towards forward defence. The need now is for in-place forces and defensive infrastructure on the eastern border, with the right capabilities deployed to stop either mass assault or infiltration in its tracks.

This should be supported by the sort of automated battle-management systems and constant technical innovation which Ukraine has successfully put in place. As Ukrainian “drone boss” Robert Brovdi put it, his country is pioneering a “new doctrine of war”.

Lesson three: Militaries benefit from reorganisation

Ukraine has abandoned the traditional independent role of armoured formations and is moving beyond the concept of infantry as a distinct arm. Its generals have realised that ground is now better held by drone teams and ground robots than vulnerable soldiers. As a result, NATO’s higher formations—divisions and even corps of 20,000-plus troops—are losing their relevance. So, if they are to achieve their intended transformation of military capabilities and associated doctrine, European militaries need to prepare to reorganise.

For the contact battle, Ukraine has adopted a much flatter command-and-control structure, based on some 110 brigades. These now have delegated funds, and the authority to procure and reduce development and production cycles from months to hours. Yet other European militaries have not begun even to experiment with such heretical innovations.

Regional air defence, of course, requires a more centralised system; Ukraine is deploying its own AI-assisted, data-driven command-and-control system. But European responses to the drone and missile threat have been predictably fragmented, with major EU states developing competing national systems and Britain electing to throw in its lot with the US company, Palantir.

As European skies lie wide open to the sort of missile and drone attacks that Russia nightly visits on Ukraine, there is no more urgent task for Europeans than to build their own systems, integrated on a regional scale and based on collective command-and-control arrangements.

Transforming for the future

Adopting such a revolutionary agenda is a huge challenge. But, as suggested in a new ECFR brief, the task is both necessary and entirely feasible. While failure to evolve does not necessarily herald imminent disaster—in fact, simply throwing (mostly borrowed) money at the new without transforming the old may well temporarily deter the mangled Russian war machine—all of Europe’s economic indicators are flashing red. As such, this approach risks becoming socially and politically unsustainable as populists exploit economic grievance.

It would be tragic if all of Europe’s efforts to bar its doors and windows against Vladimir Putin simply allowed him to achieve the domination he seeks as, aided by the Trump administration, he facilitates the rise of more Viktor Orbans across Europe.