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Nuclear Nonproliferation Treaty


The Nuclear Nonproliferation Treaty (NPT), formally called the Treaty on the Nonproliferation of Nuclear Weapons, is the cornerstone of the international effort to halt the proliferation, or spread, of nuclear weapons (State Department, United States Treaties and Other International Agreements, Vol. 21, part 1 [1970], pp. 483–494). The NPT was first signed in 1968 by three nuclear powers—the United States, the Soviet Union, and the United Kingdom—and by nearly 100 states without nuclear weapons. It came into force in 1970, and by the mid 1990s it had been signed by 168 countries.

The NPT distinguishes between nuclear-weapon states and non-nuclear-weapon states. It identifies five nuclear-weapon states: China, France, the Soviet Union, the United Kingdom, and the United States.

Article II forbids non-nuclear-weapon states that are parties to the treaty to manufacture or otherwise acquire nuclear weapons or nuclear explosive devices. Article III concerns controls and inspections that are intended to prevent the diversion of nuclear energy from peaceful uses to nuclear weapons or explosive devices. These safeguards are applied only to non-nuclear-weapon states and only to peaceful nuclear activities. The treaty contains no provisions for verification of the efforts by nuclear-weapon states to prevent the proliferation of nuclear weapons.

Under the provisions of Article IV, all parties to the treaty, including non-nuclear-weapon states, may conduct nuclear research and development for peaceful purposes. In return for agreeing not to develop nuclear weapons, non-nuclear-weapon states receive two promises from nuclear-weapon states: the latter will help them to develop nuclear technology for peaceful purposes (Art. IV), and the latter will "pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race at an early date and to nuclear disarmament" (Art. VI) (as quoted in U.S. Arms Control and Disarmament Agency 1982, 93).

Since 1975, NPT signatory countries have held a review conference every five years to discuss treaty compliance and enforcement.

North Korea has caused international concerns since 1993, with its attempts to develop a nuclear arsenal. In 1993, North Korea announced that it would withdraw from the NPT, only to rescind its withdrawal shortly thereafter. In 1994, North Korea and the United States entered into an agreement whereby the United States agreed to provide power supplies and other necessities in exchange for North Korea's promise not to pursue the development of nuclear weapons. However, in October 2002, North Korea announced that it would resume its program to develop these weapons. On January 10, 2003, it announced again that it would withdraw from the treaty, effective the following day. Although the NPT requires that nations adhere to a three-month waiting period to withdraw from the treaty, North Korea claimed that it had already done so, for it originally had announced its withdrawal in 1993. North Korea's attempts to develop nuclear weapons have brought crisis to that region, and South Korea and Japan have sought U.S. assistance to resolve the crisis through diplomacy.

further readings

Dekker, Guido den. 2001. The Law of Arms Control: International Supervision and Enforcement. Norwell, Mass.: Kluwer Law International.

Kegley, Charles W., Jr., and Eugene R. Wittkopf. 1993. World Politics. 4th ed. New York: St. Martin's Press.

Mandelbaum, Michael. 1995. "Lessons of the Next Nuclear War." Foreign Affairs (March–April).

Sheehan, Michael. 1988. Arms Control: Theory and Practice. Cambridge, Mass.: Blackwell.

U.S. Arms Control and Disarmament Agency. 1982. Arms Control and Disarmament Agreements: Texts and Histories of Negotiations.


Arms Control and Disarmament.

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Nuclear Non-Proliferation Treaty


NUCLEAR NON-PROLIFERATION TREATY (1968). Following more than a decade of discussions, on 12 June 1968 the United Nations General Assembly approved the text of a nuclear non-proliferation treaty authored primarily by representatives from the United States and the Soviet Union. On 1 July 1968 the United States, Great Britain, and the Soviet Union signed the treaty, along with fifty-nine other countries. American President Lyndon Johnson submitted the treaty to the U.S. Senate for ratification on 9 July 1968, but after the Soviet invasion of Czechoslovakia on 20–21 August 1968, the Senate was unwilling to approve any treaty with Moscow. As tensions between the superpowers cooled in early 1969, newly inaugurated President Richard Nixon resubmitted the treaty to the Senate. The Senate ratified the treaty on 13 March 1969, and Nixon signed it into law on 24 November 1969. In March 1970, the treaty took effect as international law.

The treaty had three main provisions. First, it prohibited the declared nuclear states (as of 1 January 1967)—the United States, the Soviet Union, Great Britain, France, and the People's Republic of China—from transferring nuclear weapons to nonnuclear states. Nonnuclear states were not allowed to receive or manufacture nuclear weapons. Second, the treaty protected the peaceful uses of nuclear energy by all states. International Atomic Energy Agency safeguards would assure that nuclear energy was not diverted into nuclear weapons. Third, the treaty obligated nuclear weapons states to "pursue negotiations in good faith" for "general and complete disarmament."

Only Israel, India, Pakistan, and Cuba have refused to sign the treaty. They claim that the treaty is unfair because it privileges the nuclear "haves" of the 1960s, while preventing other states from acquiring their own nuclear arsenals. India, in particular, has also accused the United States and other nations of failing to meet their stated obligation to negotiate for "general and complete disarmament." In the twenty-first century the proponents of the treaty will have to seek ways of overcoming these criticisms.


Bundy, McGeorge. Danger and Survival: Choices About the Bomb in the First Fifty Years. New York: Vintage Books, 1990.

Bunn, George. Arms Control by Committee: Managing Negotiations with the Russians. Stanford, Calif.: Stanford University Press, 1992.

———. Extending the Non-proliferation Treaty: Legal Questions Faced by the Parties in 1995. Washington, D.C.: American Society of International Law, 1994.

Garthoff, Raymond L. Détente and Confrontation: American-Soviet Relations from Nixon to Reagan. revised ed. Washington, D.C.: The Brookings Institution, 1994.


See alsoArms Race and Disarmament .

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"Nuclear Non-Proliferation Treaty." Dictionary of American History. . 18 Dec. 2017 <>.

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