Norris is a senior fellow with the Federation of American Scientists in Washington, DC. A former senior research associate with the Natural Resources Defense Council, his principal areas of expertise include writing and research on all aspects of the nuclear weapons programs of the United States, the Soviet Union and Russia, the United Kingdom, France, and China, as well as India, Pakistan, and Israel. He is the author of Racing for the Bomb: General Leslie R. Groves, the Manhattan Project’s Indispensable Man and co-author of Making the Russian Bomb: From Stalin to Yeltsin. He co-authored or contributed to the chapter on nuclear weapons in the 1985–2000 editions of the SIPRI Yearbook (Oxford University Press) and has co-authored Nuclear Notebook since 1987.
During the Cold War, the United States deployed nuclear weapons in South Korea continuously for 33 years, from 1958 to 1991. The South Korean-based nuclear arsenal peaked at an all-time high of approximately 950 warheads in 1967.
The authors estimate that as of mid-2017, there are nearly 15,000 nuclear weapons in the world, located at some 107 sites in 14 countries. Roughly, 9400 of these weapons are in military arsenals; the remaining weapons are retired and awaiting dismantlement.
India continues to modernize its nuclear arsenal, with at least four new weapon systems now under development to complement or replace existing nuclear-capable aircraft, land-based delivery systems, and sea-based systems.
The US nuclear arsenal remained roughly unchanged in the last year, with the Defense Department maintaining an estimated stockpile of some 4,480 warheads to be delivered via ballistic missiles and aircraft.
The modernization of China’s land-based nuclear-capable missile force has progressed significantly over the past year, with Beijing fielding a new version of an existing nuclear missile and a new dual-capable missile. The country has also reorganized its nuclear missile command structure.
The US nuclear arsenal remained roughly unchanged in the last year, with the Defense Department maintaining an estimated stockpile of some 4,670 warheads to be delivered via ballistic missiles and aircraft. Most of these warheads are not deployed but stored, and many are destined to be retired.