It has been over 75 years since nuclear bombs were detonated over the Japanese cities of Hiroshima and Nagasaki in August 1945, ending World War II with Japan’s unconditional surrender. Since then, one way or another, the world has avoided further use of nuclear weapons in anger, even during serious crises such as the Cuban Missile Crisis of 1962, the Yom Kippur War of 1973 and the Able Archer incident of 1983.
In 2022, the world faces a new nuclear threat, with the risk that Russian President Vladimir Putin’s invasion of Ukraine will turn into a wider war between NATO and Moscow that escalates beyond of the nuclear threshold or, alternatively, Russia’s use of a tactical nuke in Ukraine. William Burns, Director of the CIA mentioned April 14: “Given the potential desperation of President Putin and the Russian leadership, given the setbacks they have faced so far, militarily, none of us can take the threat lightly posed by a potential use of tactical nuclear weapons or low-produce nuclear weapons.
A Russian defeat at the conventional military level would increase the likelihood of Putin going nuclear, perhaps as part of a strategy of “escalate to defuse” in which a low-yield tactical nuclear weapon is detonated in Ukraine. Such a move would either seek to turn the tide of the battle or serve as a wake-up call for kyiv and NATO to accept Russia’s terms to end the war.
It is also possible that Russia decides to step up to a conventional level by extending its attacks beyond Ukraine. Sergey Lavrov, Russian Foreign Minister accused NATO to engage in a proxy war and declared that arms shipments are legitimate targets. And Russia is already making implicit threats to prolong the war to the disputed region of Transnistria Moldova. This would greatly increase the threat to NATO member Romania and destabilize the Moldovan state, many of whose inhabitants are of Romanian origin.
Perhaps most ominously, Putin recently doubled down on his nuclear rhetoric with a implied threat:
If anyone intends to intervene from the outside in current events and create strategic threats to Russia that are unacceptable to us, he should know that our retaliatory strikes will be lightning fast. We have all the tools for that, things no one else can boast of having now. And we won’t brag, we’ll use them when necessary. And I want everyone to know that.
As the West expands aid to Ukraine, the possibility that Putin could interpret it as intervention generates another path of escalation.
It is not clear how NATO would react to the use of a low-yield nuclear weapon in Ukraine or, for that matter, the large-scale use of chemical weapons against Ukrainian targets. The chemical weapons scenario is perhaps more likely, given that the norms of non-use of chemical weapons have already been eroded by Syria’s large-scale use of a series of them against its own people. in 2014. The use of such weapons by Russia could simply attract intensified sanctions and political condemnation. The tactical use of nuclear power would be quite another matter.
The use of a nuclear weapon, even a low-yield tactical weapon, would represent a fundamental change in global security. It would break the norm of non-use of nuclear weapons and, in the absence of an effective NATO response, usher in a new era in which states perceive these weapons as credible options for war, not just for deterrence.
Other nuclear-weapon states might decide to prioritize low-yield tactical nuclear weapons, and non-nuclear states that had nuclear ambitions, such as Iran, might decide that participation in non-proliferation and arms control is no longer a priority. Negotiations on reinstating nuclear deal with Iran could become a casualty of nuclear escalation in Ukraine and North Korea is already well advanced development a range of new tactical nuclear forces.
Of course, failing to respond – or reacting weakly, such as through tougher economic sanctions and political condemnation – is not the only option open to NATO should Russia use a tactical nuclear weapon in Ukraine. Direct military intervention at a conventional level, to hit Russian nuclear-capable carriers, would be an option; another would be the deployment of NATO forces on the ground to directly support Ukrainian forces in combat.
But any direct military intervention by NATO, even below the nuclear threshold, would almost inevitably lead to a wider NATO-Russia war, and with it, the near certainty of nuclear escalation. It is this specter of nuclear war – as opposed to a single detonation – that limits NATO responses, even to Russian atrocities in Bucha and Kramatorsk. In particular, the prospect of such a war degenerating into strategic nuclear exchanges and devastating the planet will be on the minds of NATO decision-makers.
Thus, there is a risk emerging now that in the face of military defeat on the conventional level, Russia will use nuclear weapons and plunge the world into a new and uncertain future. It is a future in which low-yield nuclear weapons become usable in conflict, certainly in terms of implicit and explicit coercive threats against military intervention, as China might do in a crisis in Taiwan. In the worst-case scenario, a different perception of the operational utility of low-yield tactical nuclear weapons emerges compared to strategic nuclear forces. Nuclear engineering is out of the bottle, and the question is whether it can ever be put back in.
A low-yield Russian use of nuclear weapons that would quickly lead to kyiv agreeing to Moscow-dictated terms would be the worst of all outcomes in Ukraine, at least outside of a broader war leading to a global thermonuclear war. . Moscow would change the international security order for the worse, dramatically increasing the threat of war with NATO and worsening the continent’s security outlook, while fundamentally altering perceptions of the usefulness of nuclear weapons. A key norm of the rules-based order would collapse, along with non-proliferation. Instead, Western liberal democracies should come to terms with states that viewed nuclear weapons as highly desirable capabilities for deterrence, coercion and use.
In the Indo-Pacific, we should consider the possibility of China changing or abandoning its non-use-first nuclear policy and placing greater emphasis on the development of tactical and substrategic nuclear forces for coercion and eventual use in a future Taiwan crisis.
Russia’s explicit and implicit nuclear posture sets a dangerous precedent of coercive threats, in which any response can lead to an uncontrolled escalation into nuclear war. Indeed, Moscow demonstrated a failure of Western deterrence below the threshold of strategic nuclear warfare and, at the same time, achieved escalation dominance at the tactical nuclear level. This is a lesson that will not be lost on other states.