The New Strategic Arms Reduction Treaty (New START), the last remaining U.S.-Russia nuclear treaty, expires on February 5, 2026. This expiration will mark the first time since the Cold War that no formal limits exist on the nuclear arsenals of either nation.
Signed in 2010, New START limited each country to 1,550 deployed strategic warheads and has been a critical mechanism for maintaining nuclear stability between the two nations. However, experts warn that its expiration could lead to a renewed arms race and the erosion of decades of nuclear stability.
Dr. Jim Walsh, a researcher at MIT’s Security Studies Program (SSP), cautioned: “There’ll be a turn of events a month from now, a year from now, five years from now,” he said. “Things always happen in international affairs. There’ll be a war, there’ll be a crisis.”
The treaty allowed only one extension, which was exercised in 2021 under former President Joe Biden and Russian President Vladimir Putin. President Donald J. Trump had indicated he would let the treaty expire, stating: “If it expires, it expires. We’ll just do a better agreement.”
Currently, Russia holds the largest confirmed nuclear arsenal with over 5,500 warheads, followed closely by the United States with approximately 5,044. Together, the two nations account for nearly 90 percent of the world’s nuclear weapons.
