Nuclear Arms Control, AI, and Space: Mallory Stewart at Dartmouth

On February 19, former Assistant Secretary at the U.S. Department of State Mallory Stewart visited campus to discuss a topic that has moved back into the spotlight after recent geopolitical developments: nuclear arms control. Moderated by Dickey Center Director Victoria K. Holt, the discussion featured Stewart alongside Professor Daryl Press, Dartmouth Faculty Director for the Initiative for Global Security. Mrs. Stewart drew on her past experiences serving as a Special Assistant to President Biden and Senior Director for Arms Control, Disarmament, and Nonproliferation at the National Security Council. Together, they explored the evolving challenges of nuclear deterrence, technological advancements, and international security.

The Changing Landscape of Nuclear Deterrence 

As technology advances, things become more complicated. There used to be a simple playbook on how to conduct nuclear deterrence: as long as nuclear weapons exist, and people fear them (they generally do), rogue states will be prevented from deploying them. Arms control treaties were supposed to create symmetry between adversaries, and the key principles could fit on a 3×5 index card. But the rapid advancement of military technology has dramatically undercut traditional arms control strategies. Prof. Press explained that deterrence is no longer about missile counts or second-strike capabilities. Instead, it hinges on technical factors that are increasingly difficult to verify. Small, mobile, and submarine-based nuclear arsenals introduce new vulnerabilities, making the strategic balance more precarious than during the Cold War. Risk reduction as a whole has become increasingly complex, added Mrs. Stewart. In addition, the burgeoning space domain poses new questions that remain unresolved.

The Space Question

During the Cold War, there was a mutual understanding that space was off-limits in a conventional war. Neither side would target the other’s space systems, focusing instead on direct military engagement. However, modern warfare has changed the nature of conflict. All of conventional war is now integrated with space. From space-based sensors that are used to detect the launching of nuclear weapons to space-based communication links, from space-based missile guidance systems to space-based battle damage assessments, these new strategies are now ubiquitous. It is now almost a certainty that if a serious conventional war were to break out between great powers, both sides would target each other’s space capabilities from the start. To compound the issue, Prof. Press pointed out that there are currently no existing theories on how to engage in a conventional war and at the same time convince each other not to use nuclear weapons. On the bright side, this means a lot of research remains to be done for all of the ambitious government majors.

The Ripple Effects of Nuclear Proliferation

The discussion also addressed the broader implications of nuclear proliferation among allied countries, particularly with the example of South Korea. While some South Korean leaders have expressed interest in developing nuclear weapons, this move would likely provoke strong reactions from neighboring countries such as China and undermine international nonproliferation agreements. Moves like these are never made in a vacuum: such a nuclear effort would send signals that undermine U.S. credibility. If South Korea decides they don’t trust the United States’ extended deterrence relationship, what does that tell the Japanese and our NATO allies? Why rely on Washington? Japan and the EU might also start pursuing their own nukes for their national security. Prof. Press further emphasized that nonproliferation norms could jeopardize a country’s ability to cooperate on nuclear energy, thereby disrupting economic and diplomatic relations. The secret goal of South Korean policy makers might be to strengthen nuclear coordination to have more U.S. assurance on the matter, similar to the West German nuclear shares agreement of the Cold War.

Russian Skepticism Toward Arms Control

Last but not least, the discussion emphasized the importance of understanding Russia’s perspective on nuclear strategy and arms control. After the Cold War, both the U.S. and Russia reduced their nuclear arsenals. While Russia saw its nuclear capabilities remain stagnant in the face of economic constraints, the U.S. has significantly enhanced its nuclear capabilities since the Soviet Era. These advancements have contributed to Russian skepticism toward arms control and a perception of being strategically outmatched. While this does not justify Russian aggression, it highlights how U.S. nuclear capabilities may be fueling Russian insecurity and resistance.

As both speakers emphasized, the traditional playbook for nuclear deterrence and arms control no longer applies. The integration of space-based systems, return of great power competition, and shifting of geopolitical alignments create unprecedented challenges. Addressing these issues will require original ideas. For further insights, Prof. Press’s two books Calculating Credibility: How Leaders Assess Military Threats (2005) and The Myth of the Nuclear Revolution: Power Politics in the Atomic Age (2020) can offer helpful perspectives.