One prominent casualty of Russia’s war against Ukraine is the idea that the US can safely reduce the role of nuclear weapons in its foreign policy. This idea has influenced President Joe Biden’s administration in its early thinking on foreign policy; it builds on a longer post-Cold War trend of cutting the size and centrality of America’s nuclear arsenal.
But the Ukraine crisis is revealing how central nuclear weapons remain to great-power rivalry — and reminding us that the worst weapons ever invented are indispensable to upholding the most successful international order the world has ever known.
Biden’s election elicited great expectations from the arms control and disarmament community. There was speculation that the president might make significant reductions in the US nuclear arsenal, perhaps even slash the nation’s intercontinental ballistic missile force. The administration considered, and has not publicly ruled out, a “no-first-use” or “sole-purpose” policy — essentially, a pledge that America would not initiate the use of nuclear weapons in a conventional conflict.
Yet these ideas hit resistance from American defense planners and US allies, and it is hard to see them surviving the current war.
The conflict in Ukraine serves as a case study in how US rivals plan to employ nuclear coercion in the service of revisionist objectives. Step 1: Use conventional forces to invade a vulnerable, overmatched neighbor. Step 2: Use the threat of nuclear escalation to prevent the US and its allies from getting in the way.
Putin has run this play more than once. He put his nuclear forces on alert when Russia seized Crimea in 2014, as part of an effort (almost certainly unnecessary) to deter Western military intervention. Now he has done the same thing, publicly reminding the world about Russia’s sophisticated nuclear capabilities and warning that Western interference in Ukraine would lead to “dire consequences.”
China appears to see similar utility in its growing nuclear arsenal. A possible assault on Taiwan might be followed by a nuclear alert meant to deter Washington and other powers from intervening — and, if that failed, by selective nuclear strikes or “demonstration shots” meant to coerce the US into backing down.
Chinese state media have been unambiguous on this point, declaring that, if Japan intervenes in a Taiwan conflict, “We will use nuclear bombs continuously. We will do this until Japan declares unconditional surrender for the second time.”
Regional crises could become competitions in nuclear risk-taking, which is why schemes to reduce the role of nuclear weapons in US policy are so problematic.
Extended nuclear deterrence — the threat that the US might use nuclear weapons rather than see its allies defeated in conventional wars — has long underpinned America’s alliance network. Shifting to a no-first-use or sole-purpose doctrine might have been feasible a generation ago, when Russia’s military was pathetic, and it was commonly joked that the Chinese army would need a “million-man swim” to reach Taiwan.
It is far riskier at a time when the US is struggling to shore up the military balance in Eastern Europe and the Western Pacific, and when conflict in one of those theaters would make it nearly impossible for Washington to defend, with conventional forces, its allies in the other.
If anything, the Pentagon will need more rather than fewer nuclear options. For example, it will probably require an expanded suite of “limited” nuclear options — with the ability to use small numbers of low-yield nuclear warheads against battlefield targets.
These capabilities are critical to sustaining extended deterrence by allowing Washington to threaten (even implicitly) that it might respond to regional aggression with something greater than conventional forces but less than the full weight of its strategic nuclear arsenal. More important, they will permit the US to better deter adversaries from pursuing limited nuclear escalation, by giving Washington the ability to threaten a relatively proportionate — and relatively believable — response. After all, a nuclear deterrent won’t work if your enemy is convinced you would never use it.
The Ukraine invasion should also push Washington toward a larger intellectual reckoning with the essential role that nuclear weapons play in preserving a tolerable world order.
Nuclear weapons are, in some ways, the ultimate evil — arms so powerful that their use could endanger humanity. Yet nuclear deterrence, macabre and morally absurd as it often seemed, provided the military shield behind which the free world developed during the Cold War. It thus helped create an international order that has arguably been more peaceful, prosperous and beneficial to human freedom than anything that had come before.
The central paradox of the nuclear era is that tools of unimaginable destruction contributed to an age of unprecedented human flourishing and creation. Nuclear weapons will be no less central to the struggle over world order that is unfolding today.
Bloomberg
