No abstract

The prospects for nuclear arms control appear dim following Russia’s invasion of Ukraine. Instead of continued reliance on nuclear deterrence, the resulting new awareness of nuclear risks should inform bold nuclear disarmament measures in the long term. Drawing on previous debates on ‘minimal nuclear deterrence’, this paper argues that nuclear deterrence is possible at low numbers, and hence reliance on nuclear deterrence is not an obstacle to significant progress in nuclear disarmament. In particular, there is scope for reducing the vast Russian and United States nuclear arsenals, which risk planetary-scale destruction and stand in the way of multilateral nuclear disarmament. At the same time, recent military-technological evolution has raised the bar for minimal nuclear deterrence by questioning the survivability of nuclear forces. In addition to making recommendations on how to address such strategic challenges, the paper addresses some conceptual dilemmas traditionally associated with minimal nuclear deterrence.

This paper focuses on countries under extended nuclear deterrence arrangements, or ‘umbrella’ states. The paper explores the ways in which umbrella states both in the Asia-Pacific region and in Europe have supported prevailing nuclear deterrence practices or distanced themselves from such practices. While there is a tendency for these countries to side with their nuclear-armed patron on matters related to nuclear weapons and nuclear disarmament norms, at times they have taken steps away from the allied mainstream position by advocating for anti-nuclear weapon policies. As long as extended deterrence has a nuclear dimension, allies will need to balance between normative pressures to support nuclear disarmament and alliance commitments that require at least passive support for nuclear deterrence practices.