The U.S. Nuclear Weapons Cost Study Project was completed in August 1998 and resulted in the book Atomic Audit: The Costs and Consequences of U.S. Nuclear Weapons Since 1940 edited by Stephen I. Schwartz. These project pages should be considered historical.

Global Nuclear Weapons Tests, 1945-1998

U.S. total does not include the two atomic bombs dropped on Hiroshima and Nagasaki in August 1945. The United States and the Soviet Union conducted 27 and 116 “peaceful nuclear explosions,” respectively, which are included in the above totals. To allow for accurate comparison with U.S. and U.S.S.R. testing figures and conform with the definition of a test in the 1974 Threshold Test Ban Treaty, India’s simultaneous detonations on May 11 and May 13, 1998, of (reportedly) three and two nuclear devices, respectively, are counted as two tests. Pakistan’s simultaneous detonations on May 28 and May 30, 1998, of (reportedly) five and one nuclear devices, respectively, are counted as two tests.

Sources: Natural Resources Defense Council, Nuclear Weapons Databook Project; U.S. Department of Energy; New York Times.

Copyright © 1998 The Brookings Institution