This edited volume examines the profound transformation of the global nuclear order driven by the transition from unipolarity to multipolarity. In this evolving environment, nuclear strategy, non-proliferation regimes, and coercive instruments such as sanctions and diplomatic engagements are increasingly contested by established nuclear powers and emerging regional actors alike. The volume provides a comprehensive and forward-looking analysis of how great-power competition, shifting alignments, regional rivalries, and innovative nuclear procurement strategies are reshaping deterrence stability, escalation dynamics, and governance structures within contemporary strategic warfare. It argues that multipolarity is fragmenting the traditional nuclear order and challenging long-standing assumptions regarding nuclear stability, deterrence credibility, and the capacity of international institutions to prevent proliferation. Through a series of critical inquiries, the volume explores how changing power distributions influence nuclear doctrines and escalation control, the extent to which sanctions and diplomatic negotiations remain effective in discouraging nuclear acquisition, and how new proliferation pathways emerge through clandestine technology transfers and strategic ambiguity. The book further examines the risks associated with expanding civil nuclear cooperation models, the growing significance of maritime nuclear capabilities, and nuclear latency strategies enabled by dual-use technologies.

Sarah Tzinieris, PhD, is a Lecturer in Security Studies Education within the Department of War Studies at King’s College London. She holds an MPhil and PhD in International Relations. Her interdisciplinary research examines the nexus of conflict, security, science, and technology. She also contributes to capacity-building initiatives in the field of nuclear security.

Debasish Nandy, PhD, is an Associate Professor and Coordinator of the Centre for Studies of South and South-East Asian Societies at Kazi Nazrul University, Asansol, West Bengal. He has served in visiting faculty and fellowship positions at several prestigious international institutions across Asia and Europe and has contributed extensively to the fields of international relations, Asian studies, and strategic affairs.

Monojit Das, PhD is a member, Armed Forces Tribunal (Principal Bench) Bar Association,Delhi, India