Background of U.S. Efforts to Dispose of Surplus Fissile Materials

Since the end of the Cold War, the United States has significantly reduced the size of its nuclear weapons arsenal. As a result of these reductions, large quantities of plutonium and highly enriched uranium have become surplus to defense needs. The mission of the National Nuclear Security Administration’s Office of Fissile Materials Disposition is to dispose of surplus U.S. highly enriched uranium (HEU) and surplus U.S. weapon-grade plutonium and support Russia’s disposition of its surplus weapon-grade plutonium. This paper presents a historical context of U.S. fissile materials disposition efforts, discusses options that were considered, and provides a perspective on how these disposition efforts have evolved.