Plus Ça Change? Prospects of a Nuclear Deterrence Multipolarity in Southern Asia

ABSTRACT Some scholars assess that Southern Asia comprises a nuclear chain or a deterrence trilemma. Although the region is home to three states with nuclear weapons, there is only one clear nuclear deterrence dyad. India and Pakistan have explored the contours of nuclear deterrence in several past military crises, while nuclear weapons have been notably absent from recent Sino-Indian border tensions. What factors or developments might push the region toward a nuclear deterrence multipolarity? The key variable is the India–China relationship and the extent to which nuclear weapons become more prominent in respective national security belief systems in New Delhi and Beijing. Notable trends already favor such a development, including changing geopolitics in the region, the rise of nationalist domestic politics, technology competition, and growing crisis escalation concerns. Two fulcrums that might tip the region from the status quo into a deterrence multipolarity are parallel nuclear posture changes in India and China that create nuclear coupling, and hardening of geopolitical alignments into more adversarial blocs. Preventing deterrence multipolarity through new nuclear confidence-building measures will be difficult owing to divergent interests, power and institutions in the region. Upgrades to existing nuclear CBMs may be more politically feasible. Even in the absence of new nuclear CBMs, however, China, India, and Pakistan could build predictability in the region and mitigate potential sources of conflict through new measures to manage common-pool resource competition, dangerous behaviours in space, and a range of crises and emergencies.