READ FULL REPORT Russia’s invasion of Ukraine has illuminated longstanding cracks in the nuclear arms control regime. Legacy arms control tools had little utility as Russia eschewed arms control agreements and transparency-based risk reduction measures designed to avoid unwanted escalation. Russian aggression has included direct and indirect nuclear threats, such as Russian president Vladimir Putin’s statement on September 21, 2022: “They [NATO] have even resorted to the nuclear blackmail. . . . I would like to remind those who make such statements regarding Russia that our country has different types of weapons as well.” Russia’s invasion of Ukraine is forcing a reckoning for the arms control community on the utility of arms control and risk reduction tools, many of which are designed to lower the chances of inadvertent escalation, in the face of an actor who intentionally escalates crises and uses nuclear weapons for coercion. This reckoning comes as the United States also wrestles with how to deter two peer competitors, given China’s growing strategic arsenal and regional ambitions. In 2020, U.S. Strategic Command (STRATCOM) commander Admiral Charles Richard stated, “We are on a trajectory for the first time in our nation’s history to face two peer nuclear-capable competitors who have to be deterred differently, and we’re working very hard to meet that challenge.” And the 2022 U.S. National Defense Strategy outlines the need to compete with China as a pacing challenge while accounting for the acute threat from Russia. If arms control is to have a future, it will have to work in tandem with these changing deterrence requirements. In January 2022, the Project on Nuclear Issues published a study, Integrated Arms Control in an Era of Strategic Competition, that offered a vision for the future of arms control evolving in parallel with integrated deterrence. Integrated arms control may go beyond the rigid structures that have shaped legacy U.S.-Russia arms control agreements by adopting new modalities, incorporating new systems, and including new actors. This policy paper applies the principles of integrated arms control to the changing deterrence landscape and argues that because arms control and deterrence work hand in hand, future U.S. arms control efforts will have to adapt to the changing strategic necessity of deterring two peer competitors. However, arms control remains a path worth pursuing because of its benefits to strategic stability, risk reduction, transparency, and predictability. How the United States and arms control partners apply these principles will be determined by a variety of factors, including the outcome of the war in Ukraine and U.S. decisions about force posture. To be clear, prospects for arms control in the short term are not a cause for optimism; rather, this paper is intended as a first step in identifying the key questions that will determine the role of arms control while deterring two peer competitors. This paper will first examine ways that the war in Ukraine may impact prospects for arms control, then pose first-order questions about future U.S. arms control policy. In so doing, it assumes Russia will remain a peer strategic competitor with a sizeable nuclear arsenal. Even if Russia emerges from the Ukraine crisis with significantly depleted conventional forces, its nuclear arsenal will be of even greater importance. The paper also assumes that China will continue on its current trajectory of expanding its strategic arsenal. It concludes that balancing integrated arms control and integrated deterrence in the face of two peer competitors should focus on five priorities: 1) tailoring arms control to match deterrence requirements; 2) developing short-term risk reduction measures; 3) furthering allies’ strategic priorities; 4) continuing U.S. strategic modernization; and 5) competing in emerging technologies while also exploring arms control opportunities. Heather Williams is the director of the Project on Nuclear Issues and a senior fellow in the International Security Program at the Center for Strategic and International Studies (CSIS) in Washington, D.C. Nicholas Adamopoulos is program manager and research associate with the Project on Nuclear Issues at CSIS. This research was made possible through the support of the United States Office of the Deputy Assistant Secretary of Defense Threat Reduction and Arms Control (ODASD(TRAC)). The opinions, findings, views, conclusions, or recommendations contained herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of ODASD(TRAC) or the U.S. government –