Working Group 1:

Understanding and Mitigating Pathways to Nuclear War

The core objective of this working group is to identify possible pathways to nuclear war, examine their degree of probability, and find ways of plugging the gaps to minimize the chances of deterrence breakdown.


Working Group Co-Chairs

Prof. Matthew Bunn

Harvard Kennedy School

Dr. Manpreet Sethi

Center for Air Power Studies

Baselines & Questions

The contemporary nuclear landscape is dotted by several worrying features: existence of multiple nuclear dyads (some elongating into strategic chains, creating multipolar nuclear tensions); increasingly hostile relations among some nuclear-armed states; evolving technologies that may increase nuclear risks; ongoing nuclear modernisation that reflects continuing or increasing reliance on nuclear weapons in nuclear-armed states; unresolved territorial and security disputes among nuclear-armed states; doctrines in some states that suggest increased reliance on nuclear weapons; states that seem to believe that creating nuclear risks is useful for achieving their deterrence or foreign policy objectives; and the possibility of conventional war in nuclear shadow.


Each one of these conditions, individually or collectively, could create pathways to nuclear war. Russia’s invasion of Ukraine and its nuclear sabre-rattling highlight many of these issues, seeming to suggest a more aggrieved and risk-acceptant Russian leadership, whose damaged conventional forces may force increased Russian reliance on nuclear weapons in the future. This WG, therefore, has an urgent task.

Questions for the Working Group

  • What are the most dangerous pathways by which a nuclear war might start? How does this vary from one set of potential nuclear adversaries to another?
  • What factors are most important in increasing or decreasing the risk of nuclear conflict?
  • What characteristics of nuclear forces and policies (alert levels, command approaches, dual use systems, doctrines on when and how nuclear weapons would be used, etc.) increase or decrease the risk of nuclear war? What kinds of doctrines and postures can provide deterrence with minimum risk of nuclear war?
  • How can nuclear deterrence be “extended” to allies while maintaining minimum risk of nuclear use?
  • What actions, done for deterrence or defense, might actually provoke an adversary to take actions that might lead to the use of nuclear weapons?
  • How are evolving technologies affecting strategic balances and the risk of nuclear conflict, and how could any increase in risk from evolving technologies best be mitigated? On this question, our work will overlap with that of the WG on evolving technologies and the future of arms control.
  • How will changing geopolitics, and a more multipolar world affect the various potential pathways to nuclear war?
  • Last but perhaps most important, what could states do to reduce these dangers, along each of the pathways identified as especially dangerous, in each of nuclear regions?

Working Group Members

Dr. Rabia Akhtar, Nonresident Senior Fellow at the Atlantic Council South Asia Center and Director, Centre for Security, Strategy and Policy Research, University of Lahore

Dr. James Acton, The Jessica T. Mathews Chair and Co-Director of the Nuclear Policy Program at the Carnegie Endowment for International Peace

Mr. Andrei Baklitsky, Senior Researcher on WMD

Ambassador Linton Brooks, independent consultant on national security issues, senior adviser at CSIS, Distinguished Research Fellow at the National Defense University, and Adviser to four of the U.S. Department of Energy national laboratories

Dr. Mariana Budjeryn, Senior Research Associate, Project on Managing the Atom, Belfer Center, Harvard Kennedy School, Harvard University

Brig. Gen. Feroz Khan, Research Professor, Naval Postgraduate School, Department of National Security Affairs

Dr. Ariel Levite, nonresident senior fellow in the Nuclear Policy Program and Technology and International Affairs Program at the Carnegie Endowment, former deputy director general for policy at the Israeli Atomic Energy Commission

Prof. Rose McDermott, The David and Mariana Fisher University Professor of International Relations at Brown University and a Fellow in the American Academy of Arts and Sciences

Lt. Gen. Prakash Menon, Director Strategic Studies Programme, Takshashila Institution, Bangalore

Dr. Tong Zhao, Senior Fellow in the Nuclear Policy Program at the Carnegie Endowment for International Peace and Visiting Research Scholar at Princeton University’s Science and Global Security Program