For decades, the United States has led the effort to stem the spread of nuclear weapons, both among potential adversaries and among its allies and partners. The current state of deterrence and of the nonproliferation regime, however, is open to many doubts. What happens if the nonproliferation regime should break down altogether? What happens if extended deterrence should fail, and allies no longer believe in the credibility of the U.S. nuclear umbrella? What happens when the world has not 9 but 11, 15, 18, or even more nuclear powers? This study explores how such a world might function and what it would mean for our present conceptions of deterrence, for the place of the United States in the international order, and for international order itself.

Project Atom is a forward-looking, "blue-sky" review of U.S. nuclear strategy and posture in a 2025-2050 world in which nuclear weapons are still necessary. The report highlights and addresses the current deficit in national security attention paid to the continued relevance and importance of U.S. nuclear strategy and force posture, provides a new open-source baseline for understanding the nuclear strategies of other countries, and offers a credible, intellectually tested, and nonpartisan range of options for the United States to consider in revising its own nuclear strategy.

The National Defense Authorization Act of 2016 mandates a review of missile defeat policy, strategy, and capability to be completed by January 2018. This upcoming Missile Defeat Review (MDR) represents an opportunity for the Trump administration to articulate a vision for the future of air and missile defense. This collection of expert essays explores how the strategic environment for missile defense and defeat has evolved since 2010 and offers recommendations to help guide and inform the MDR's development.