Nonproliferation, according to the State Department, is a policy of preventing the spread of nuclear and other weapons of mass destruction, and their means of delivery.

Nonproliferation Treaty:
At the close of World War II, the nations of the world began a series of attempts to limit the spread of nuclear weapons. These efforts were largely unsuccessful, leading up to the Cuban missile crisis in 1962. During the sixties, efforts through the UN at creating an international nonproliferation treaty were blocked by Soviet objection to a multilateral nuclear force within the NATO nations and American insistence on these "collective defense arrangements". The Soviet Union eventually agreed to provisions that allowed U.S. missiles to be placed on the territory of non-nuclear NATO members. In 1968, the Treaty on the Non-Proliferation of Nuclear Weapons (aka NPT) was signed by the US, the USSR, the UK, and 59 other countries. It finally entered into force in 1970. It provided provisions to prevent the spread of nuclear weapons, with monitoring provided by the International Atomic Energy Agency (IAEA). As of 2002, the treaty had 187 signatory nations, with the notable exceptions of India, Pakistan and Israel.

The doctrine of nonproliferation has served the world well for the past half century, but as demonstrated by the crises in Iraq and Korea, its limits are being reached.

Nuclear States:
1945 United States
1949 Soviet Union
1952 United Kingdom
1960 France
1964 China

1967? Israel
1974 India
1979 South Africa (dismantled in 1991)
1998 Pakistan
2002 North Korea?

"Non-Proliferation Treaty" from the U.S. Department of State at

"Non-Proliferation treaty explained", BBC News, 10 January, 2003,

Center for Defense Information

The Carnegie Endowment for Peace at

"The State of Nuclear Proliferation 2001", from the Arms Control Association at