Since launching its full-scale invasion of Ukraine, Russia has conducted an intense campaign of nuclear signalling and threats designed to provide it with a strategic advantage. The Kremlin aims to not only deter the West from directly interfering in its attempts to conquer Ukraine but also to limit Western political, economic, and military support for the country.
Moscow has been particularly successful in this: not only has NATO refrained from direct intervention – such as by setting up a no-fly zone – but Western nations have avoided forms of military assistance for Ukraine that fall within their rights as third parties in the conflict. For instance, Poland and the United States agreed in March 2022 not to deliver Polish Mig-29 fighter jets to Ukraine. The US and other NATO countries appear to have been restrained by fear of a direct confrontation with Russia.
In contrast, the Soviet Union supplied fighter jets in large quantities to North Korea and Vietnam when each country was at war with the US, and to Egypt and Syria when they were at war with Israel. None of this triggered nuclear escalation or threats from the US in response.
Slovakia now plans to donate its Mig-29s to Ukraine. And such support will not cause NATO to stumble into a third world war. This was true in March and will remain true.
The Biden administration has restricted the range of ammunition it provides to Ukraine with the M-142 HIMARS multiple rocket launcher to 80km (the M-30 series of munition), withholding longer-ranged MGM-140 ATACMS. The administration has also demanded that Ukraine avoid strikes on targets in Russian territory (even though facilities supporting the Russian war effort there would be legitimate military targets under the Hague and Geneva conventions).
After Secretary of Defence Lloyd Austin declared on 24 April that Russia needs to be weakened to the point that it could not bully its neighbours, President Joe Biden wrote in the New York Times that the US would not use the war to inflict more damage on Russia than was necessary to halt the invasion. This prompted widespread speculation about whether the war aims of the White House differed from those of the state and defence departments.
Fear of nuclear escalation is even more apparent in some western European capitals than in Washington. German Chancellor Olaf Scholz stated in April that “there must not be a nuclear war” as a defence of his reluctance to supply Ukraine with heavy weapons. He decided that Germany would only deliver certain systems – main battle tanks and infantry fighting vehicles – to its eastern European allies so that they could provide Soviet-era systems to Ukraine. Militarily, these swap deals make no sense, as they only delay assistance to Ukraine and provide it with inferior materiel.
French President Emmanuel Macron later stated that it was “almost” NATO policy not to supply certain weapons systems to Ukraine, hinting that other Western European governments shared Berlin’s views. But this is an incoherent approach to the challenge. A modern Panzerhaubitze 2000 howitzer of the kind Germany has now supplied to Ukraine is far more lethal than a 1970s-era Leopard 1 main battle tank. The former has a much greater range than the latter, potentially allowing it to strike targets in Russia. Nonetheless, Germany will not provide Ukraine with the Leopard 1 because it is a particular class of weapon. Such arbitrary restrictions cannot have come from military advice or from independent risk-benefit calculations. Rather, they seem to have come from Russian President Vladimir Putin’s threats to escalate if the West supplied Ukraine with certain systems.
Current Western efforts to supply Ukraine with heavy weapons are just enough to keep it in the fight. But they will not allow the country to recapture its territory and defeat the Russian military. Privately, politicians and officials from various European countries have told this author of their belief that Russia could or would use nuclear weapons if it faced the prospect of defeat in Ukraine. It is conceivable that this fear is the main restraint on their support for Kyiv.
However, these fears are unjustified. Nuclear warfare against Ukraine makes no sense. A single nuclear strike would not alter the military balance in the war. The use of multiple nuclear weapons would do so, but would also inflict huge and lasting damage on Russia. Nuclear attacks on a NATO country would begin escalation that Russia could not control. And the Russian military would be unable to respond to any other contingency, because it would be bogged down in Ukraine. Russia could only respond to retaliation for a nuclear strike with further nuclear escalation – which would be suicidal. Putin is certainly not concerned with morals or ethics, but he is far from crazy or suicidal.
One could always have anticipated that Putin would use a nuclear scare to influence the West’s position. However, it is surprising how successful his approach has been. This is the first time a state has used the threat of nuclear weapons to engage in a colonial conflict or a war of expansion. France did not threaten to use nuclear weapons against states that backed Algerian nationalists or the Viet Minh. Nor did the United Kingdom threaten Argentina in this way during the Falklands war. The Soviet Union did not resort to nuclear threats during its Afghanistan campaign. Nor did the US in Vietnam, Iraq, or Korea. None of the diplomats who negotiated the Nuclear Non-Proliferation Treaty (NPT) – be they Western, Soviet, or non-aligned – appeared to consider that a state would use nuclear threats as cover for expansion into the territory of a non-nuclear state.
Putin’s threats will fundamentally alter cost-benefit calculations on nuclear non-proliferation in many capitals. For example, Iran – which is slowly developing the capability to produce a nuclear weapon at short notice – now has a pretext to rethink its nuclear commitments.
Meanwhile, Western countries’ overly cautious approach to military assistance will concern countries that have tried to strengthen their political and economic ties with them in exchange for security. Sweden and Finland could quickly join NATO, a nuclear alliance. But many other countries cannot. They now know that the world outside formal defence pacts will be brutal and cynical. European non-nuclear states – some of which abandoned nuclear weapons programmes in the 1970s and joined the NPT in good faith – have not emphasised this point enough when calling on countries such as Argentina and South Africa to isolate Russia. They need to explain to them, and to voters at home, why a world in which great powers build empires in the shadow of the bomb will be even more dangerous one than one in which Russia loses its war on Ukraine.
The European Council on Foreign Relations does not take collective positions. ECFR publications only represent the views of their individual authors.