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The Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space and Under Water, or the Partial Test Ban Treaty (PTBT) was signed by the Original Parties (the Union of Soviet Socialist Republics, the United Kingdom of Great Britain and Northern Ireland and the United States of America) on 5 August 1963. It opened to all other Member States for signature on 8 August 1963 and entered into force on 10 October 1963. Today 126 states are parties to the PTBT.
The PTBT preceded the Treaty on the Nonproliferation of Nuclear Weapons (NPT) of 1968 and the Comprehensive Test Ban Treaty (CTBT) of 1996. It was conceived of as a step towards general and complete disarmament. In the midst of expansive nuclear weapon testing through the late 1950s and early 1960s, in which testing was unregulated by international law, a strong opposition movement to testing came about calling for a complete ban on nuclear testing. Country leaders, like Kennedy and Khrushchev were against a comprehensive ban as they saw testing as imperative for their national security. They negotiated a partial test ban. V. Mastny, ‘The 1963 Nuclear Test Ban Treaty: A Missed Opportunity for Détente?’ 10 Journal of Cold War Studies, 1 (2008), 3-25.
The PTBT is a product of decades of negotiation and a milestone in the nonproliferation effort. The efforts for a treaty on testing began in 1946 with United Nations General Assembly Resolution 1(I) which founded the UN Atomic Energy Commission (UNAEC). Later that year, the US proposed the Baruch Plan to the UNAEC. The plan called for the creation of an Atomic Development Authority to oversee research, development, and use of nuclear technology and inspect states' nuclear facilities. It was opposed by the USSR, however, as it was seen as a step by the U.S. towards nuclear dominance. The USSR abstained from the vote, preventing it from passing. In 1952, the UNAEC was dissolved and the UN Disarmament Commission (UNDC) was established by General Assembly Resolution 502 (IV). The resolution directs the UNDC to draft proposals on the regulation, limitation and reduction of all armaments, the elimination of all weapons of mass destruction, and the regulation of atomic energy, to be used only for peaceful purposes.
In March of 1954 the US performed a thermonuclear test at Bikini Atoll. The power of the weapon and subsequent extent of radiation was underestimated and led to contamination of people in the area and public outrage. A.R. Divine, ‘Early Record on Test Moratoriums’, 42 Bulletin of the Atomic Scientists 5 (1986), 24. Meanwhile, the international community had grave concerns about nuclear weapon testing. Indian Prime Minister Jawaharlal Nehru proposed a Comprehensive Nuclear-Test-Ban Treaty (CTBT) to the United Nations Disarmament Commission on 29 July 1954. This was the first international call for a complete ban on nuclear weapon testing. D. Kimball & S. Taheran, ‘Nuclear Testing and Comprehensive Test Ban Treaty (CTBT) Timeline’, September 2016. The outrage about testing led to the bilateral moratorium of 1958 in which both the US and USSR agreed to temporarily stop testing.
The bilateral moratorium was a start, but the efforts against nuclear weapon testing continued. In May of 1955, the UNDC held a subcommittee of the United States, the United Kingdom, Canada, France, and the Soviet Union. 'Efforts to negotiate an international agreement to end nuclear tests began when the Soviet Union included discontinuance of weapons tests in its proposals.' The Soviet proposal was key in bringing the testing bans conversation to the forefront of the nuclear states. Both sides began negotiating bans on nuclear weapon testing.
The USSR proposed a complete testing ban, but the US opposed as they could not verify other states’ compliance. In response, the US called for an international commission for verification, to ensure that tests were not being conducted. In June of 1957 the USSR proposed a plan including an international verification system. While details on the verification system were discussed, the USSR in March 1958 announced a voluntary ban on testing (Burr Montford 2003). Khrushchev called on President Eisenhower to also halt testing but the US continued. With the pressure of the USSR ban, President Eisenhower with British Prime Minister Harold Macmillan and Khrushchev agreed to hold a conference on the issues regarding a monitoring system for test bans. W. Burr & H. Montford (eds.), The Making of the Limited Test BanTreaty, 1958-1963’, The National Security Archive, 8 August 2003. Later in 1958, the Geneva Conference of Experts met to discuss a ban on nuclear testing and how to effectively monitor nuclear testing. Experts from the US and USSR met to discuss a verification system and produced a report on seismic and atmospheric testing. W. Burr & H. Montford (eds.), ‘The Making of the Limited Test BanTreaty, 1958-1963’, The National Security Archive, 8 August 2003. The report influenced representatives from the US and USSR to negotiate a short term yearly moratorium on testing, contingent on each others compliance. W. Burr & H. Montford (eds.). ‘The Making of the Limited Test BanTreaty, 1958-1963’, The National Security Archive, 8 August 2003. Testing was halted from 1958-1961 when the USSR announced it would commence testing again.
The Cuban Missile Crisis in October 1962 served as a turning point. It reiterated the seriousness of nuclear weapons and also renewed public outrage on nuclear weapons. W. Burr & H. Montford (eds.). ‘The Making of the Limited Test BanTreaty, 1958-1963’, The National Security Archive, 8 August 2003. Shortly after, negotiations between the US and USSR began. These talks, headed by President John F. Kennedy and Nikita Khrushchev between 1962-1963 led to the Partial Test Ban Treaty. The goal was to negotiate a comprehensive test ban treaty but the two sides could not agree on a comprehensive agreement. Instead they proposed a partial agreement in which they agreed to ban all testing except that performed underground, where the radiation would not spread outside their own territory. D. Kimball & S. Taheran, ‘Nuclear Testing and Comprehensive Test Ban Treaty (CTBT) Timeline’, September 2016. A major motivation to sign the treaty for both sides was the threat of proliferation. The US was concerned over China’s nuclear weapon program and saw the Partial Test Ban Treaty as a way to curb or at least monitor their proliferation. W. Burr & H. Montford (eds.). ‘The Making of the Limited Test BanTreaty, 1958-1963’, The National Security Archive, 8 August 2003. The USSR was concerned about China as well and also about East Germany and their possible alliance with the US which would threaten the USSR’s national security. W. Burr & H. Montford (eds.). ‘The Making of the Limited Test BanTreaty, 1958-1963’, The National Security Archive, 8 August 2003. China was not interested in limiting their testing capabilities as they saw nuclear weapon development as essential to strengthening national security and 'enhancing' international status. B. Garrett, B. Glaser, 'Chinese Perspectives on Nuclear Arms Control’ 20 International Security 3 (1995), 43-78 (restricted access). Despite these concerns, the Partial Test Ban Treaty was successfully negotiated.
The Partial Test Ban Treaty is a legally binding instrument which 'prohibits nuclear weapon testing in the atmosphere; beyond its limits, including outer space; or under water, including territorial waters or high seas; or in any other environment if such explosion causes radioactive debris to be present outside the territorial limits of the State under whose jurisdiction or control such explosion is conducted'. 1963 Partial Test Ban Treaty, Article 1. The PTBT applies to all 105 signatory Member States. Status of the 1963 Partial Test Ban Treaty. France and China were the only nuclear weapon states to not sign. All nuclear weapon states have signed the Comprehensive Test Ban Treaty. 1996 Comprehensive Test Ban Treaty. The PTBT is of 'unlimited duration' and applies to the atmosphere, outer space, under water, and any area within a states jurisdiction at which a nuclear test has the potential to contaminate other states. The PTBT was enhanced by the adoption of the Comprehensive Test Ban Treaty on 10 September 1996 although the CTBT will not enter into force until more states ratify it including China and the US. 1996 Comprehensive Test Ban Treaty.
Last updated on: 20 July 2017