Amy F. Woolf
Nonresident Senior Fellow, Atlantic Council
Introduction
When the New Strategic Arms Reduction Treaty (New START) expired on February 5, 2026, the United States and Russia were left without any legally binding restrictions on their nuclear forces. The United States and Soviet Union had opened the era of arms control in the 1960s and eventually negotiated several agreements that restrained their competition and reduced their forces. This process was one of the more visible elements of the post-1945 nuclear order that sought to mitigate the risks created by the existence of nuclear weapons.