Nuclear weapons of the United States

The United States detonated the first nuclear weapon at Alamogordo in July 1945 and remains the only state to have used nuclear weapons in war, against Hiroshima and Nagasaki the following month. Its inventory of roughly 5,040 warheads comprises a military stockpile of about 3,700, with some 1,340 retired warheads awaiting dismantlement. Around 1,770 warheads are deployed: about 1,670 on strategic delivery systems, plus an estimated 100 B61 gravity bombs forward-based in Europe under NATO nuclear sharing.

The force is a full triad. Some 400 Minuteman III missiles sit in silos across five states; 14 Ohio-class submarines carry Trident II D5 missiles and the majority of deployed warheads; 46 of the 76 B-52H bombers and all 19 B-2As are nuclear-capable, delivering cruise missiles and gravity bombs. The B61-12 bomb completed production in December 2024, and every leg is now being replaced at once, with the Sentinel ICBM, Columbia-class submarines, the B-21 Raider bomber, the LRSO cruise missile and the B61-13 bomb, in the largest modernization program since the Cold War. The megaton-class B83-1 remains in the active stockpile despite direction to retire it.

Washington extends nuclear guarantees to NATO and to allies in Asia. It observed New START limits until the treaty expired in February 2026; with no successor in force, US strategic forces are treaty-unconstrained for the first time in five decades. The administration rejected Putin's offer of a one-year extension of the old limits and instead seeks a new trilateral agreement including China, which it raised at the Beijing state visit of 14 and 15 May 2026 and at the White House meeting with Xi on 24 September 2026; China has not engaged.

The rebuild is straining. The Sentinel program has slipped years behind schedule and far past its budget baseline, forcing a restructuring: its projected cost is about 141 billion dollars, its first flight test is due before March 2028 and initial operational capability has moved from fiscal 2029 to around fiscal 2033. Delivery of the lead Columbia-class boat has slipped to about March 2029. The B61-13, a higher-yield bomb variant announced in 2023, reached its first production unit in May 2025, a year ahead of schedule, with production to conclude around fiscal 2028. The LRSO has logged four successful flight tests since early 2025 ahead of a first production unit in fiscal 2027, a nuclear sea-launched cruise missile is in development for the early 2030s, and the W93 warhead has been in its design phase since March 2025.

On 30 October 2025 the president ordered the Pentagon to start testing nuclear weapons on an equal basis with other powers; the Energy Department subsequently described system and non-nuclear tests, and no US explosive test has been conducted. On 1 October 2026 the NNSA ran a non-nuclear chemical-explosive detection experiment at the Nevada National Security Site. Since New START lapsed, Washington has kept deployed numbers near the old ceiling but openly studies uploading stored warheads onto existing missiles, and the Golden Dome homeland missile-defense initiative launched in 2025 adds a new variable to strategic stability. In Europe, the UK joined NATO's nuclear air mission with F-35A purchases in June 2025 amid a revived deterrence debate.