Nuclear Testing

Modules:

Module 2:

Banning Nuclear Tests

Updated: 2023

1. Why comprehensively ban nuclear testing?

Throughout the Cold War, governments sought to ban or at least limit nuclear tests as an essential step in drawing down the arms race, stopping the proliferation of nuclear weapons, and reducing environmental damage:

  • In 1954, the Japanese Parliament called for a halt to nuclear testing after the crew of a fishing vessel were exposed to significant fallout from the U.S.’ Castle Bravo atmospheric test. [1] Speaking just over a month after the Castle Bravo test, Prime Minister Jawaharlal Nehru of India called for the cessation of nuclear testing, and later submitted a proposal for negotiations toward a nuclear test-ban treaty for consideration at the UN Disarmament Commission. [2] [3]
  • Opened for signature in 1963, the Partial Test Ban Treaty banned nuclear tests in the atmosphere, underwater, and in outer space, effectively restricting signatory nuclear states (U.S., UK, and USSR) to underground testing. [4] The treaty text noted the underlying desire to “put an end to the armaments race and eliminate the incentive to the production and testing of all kinds of weapons, including nuclear weapons.” [5] In a show of support for these objectives, numerous countries with no nuclear weapons programs also ratified the treaty.
  • In 1974, the U.S. and the Soviet Union signed the Threshold Test Ban Treaty, committing them not to test nuclear weapons having a yield in excess of 150 kilotons. The treaty preamble reaffirmed the signatories’ commitments to the Partial Test Ban Treaty and highlighted objectives common to both treaties, including “the intention to achieve at the earliest possible date the cessation of the nuclear arms race.” [6] Although the two countries ratified the treaty in 1990, both expressed their intent to respect the treaty limits in 1976. [7]
  • In 1995, the commitment of nuclear weapon states to pursuing a Comprehensive Nuclear-Test-Ban Treaty (CTBT) was instrumental in securing the necessary votes for the indefinite extension of the Treaty on the Nonproliferation of Nuclear Weapons (NPT). [8] [9]

2. What is the Comprehensive Nuclear-Test-Ban Treaty (CTBT)?

Negotiated by the United Nations Conference on Disarmament in 1996, the CTBT is designed to prohibit all nuclear weapons test explosions and other nuclear explosions (including underground tests and peaceful nuclear explosions, which were not prohibited by the LTBT). [10]

States Parties agree:

  • Not to conduct any nuclear explosions, or assist with or encourage any other states in conducting any type of nuclear explosion.
  • To establish and participate in the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), which will be responsible for the implementation and verification of the treaty.  [11]

Nuclear weapons design tests can still occur as long as they are “zero-yield,” meaning that an inert substance could be used in place of the fissile material to test the functionality of the nuclear device. No nuclear yield occurs in such tests. [12]

3. What is required for the CTBT to enter into force?

  • All 44 countries listed in Annex II of the CTBT must sign and ratify the treaty for it to enter into force.
  • When treaty negotiations were concluded in 1996, these 44 countries were selected as necessary for entry into force because they participated in the treaty’s negotiations and had significant nuclear technology of some kind (at least one nuclear power or research reactor, but in some cases nuclear weapons). [13]
  • Of the 196 UN member states, 186 states have signed the treaty and 177 have ratified it. [14] However, the treaty has not entered into force because 8 Annex II states have not yet signed and/or ratified the treaty:
    • The United States, China, Egypt, Iran, and Israel have signed, but not yet ratified the treaty.
    • North Korea, India, and Pakistan have neither signed nor ratified the treaty. [15]
    • The latest state to ratify the Treaty is the Solomon Islands on January 20, 2023. [16]

4. What are countries’ arguments against joining the CTBT?

For entry into force to be possible the objections of the 8 remaining Annex II states to signing and/or ratifying the treaty must be successfully addressed. Some states’ terms for joining the treaty are more clearly defined than others.

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Sources

[1] Rebecca Johnson, “Unfinished Business: The Negotiation of the CTBT and the End of Nuclear Testing,” UNIDIR/2009/2, p. 11, http://www.unidir.org/files/publications/pdfs/unfinished-business-the-negotiation-of-the-ctbt-and-the-end-of-nuclear-testing-346.pdf.
[2] Rebecca Johnson, “Unfinished Business: The Negotiation of the CTBT and the End of Nuclear Testing,” UNIDIR/2009/2, p. 11, http://www.unidir.org/files/publications/pdfs/unfinished-business-the-negotiation-of-the-ctbt-and-the-end-of-nuclear-testing-346.pdf.
[3] Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization, “Page 4: Nuclear Testing: 1945-2009,” https://www.ctbto.org/nuclear-testing/history-of-nuclear-testing/nuclear-testing-1945-today/page-4-nuclear-testing-1945-2009/.
[4] U.S. Department of State, “Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space and Under Water,” 1963, http://www.state.gov/t/isn/4797.htm#treaty.
[5] U.S. Department of State, “Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space and Under Water,” 1963, http://www.state.gov/t/isn/4797.htm#treaty.
[6] U.S. Department of State, “Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space and Under Water,” 1963, http://www.state.gov/t/isn/4797.htm#treaty.
[7] U.S. Department of State, “Treaty Between the United States of America and The Union of Soviet Socialist Republics on the Limitation of Underground Nuclear Weapon Tests (and Protocol Thereto) (TTBT),” http://www.state.gov/t/isn/5204.htm#treaty.
[8] Jayantha Dhanapala, Randy Rydell, “Multilateral Diplomacy and the NPT: An Insider’s Account,” UNIDIR/2005/3, p.1-4, http://www.unidir.org/files/publications/pdfs/multilateral-diplomacy-and-the-npt-an-insider-s-account-323.pdf.
[9] Tariq Rauf, Rebecca Johnson, “After the NPT’s Indefinite Extension: The Future of the Global Nonproliferation Regime,” The Nonproliferation Review (Fall 1995): p. 31, https://www.nonproliferation.org/wp-content/uploads/npr/raufjo31.pdf.
[10] Preparatory Commission for the Comprehensive Nuclear Test-Ban Treaty Organization, Who We Are, Accessed November 13, 2015, http://www.ctbto.org/specials/who-we-are/.
[11] Preparatory Commission for the Comprehensive Nuclear Test-Ban Treaty Organization, “Comprehensive Nuclear Test-Ban Treaty,” Treaty Text, Preparatory Commission for the Comprehensive Nuclear Test-Ban Treaty Organization, Accessed November 13, 2015, http://www.ctbto.org/fileadmin/content/treaty/treaty_text.pdf.
[12] Tom Z. Collina and Daryl G. Kimball, “Test Ban Treaty: Myths vs. Realities,” Arms Control Association, Vol. 3, Issue 6, March 30, 2012, www.armscontrol.org; “Nuclear Weapon Testing,” Federation of American Scientists, July 9, 2000, www.fas.org.
[13] Preparatory Commission for the Comprehensive Nuclear Test-Ban Treaty Organization, 1994-96: Entry Into Force Formula, Accessed November 13, 2015, http://www.ctbto.org/the-treaty/1993-1996-treaty-negotiations/1994-96-entry-into-force-formula/.
[14] Preparatory Commission for the Comprehensive Nuclear Test-Ban Treaty Organization, Status of Signature and Ratification, Accessed July 6, 2023, https://www.ctbto.org/our-mission/states-signatories.
[15] Preparatory Commission for the Comprehensive Nuclear Test-Ban Treaty Organization, Status of Signature and Ratification, Accessed July 6, 2023, https://www.ctbto.org/our-mission/states-signatories.
[16] Preparatory Commission for the Comprehensive Nuclear Test-Ban Treaty Organization, Status of Signature and Ratification, Accessed July 6, 2023, https://www.ctbto.org/our-mission/states-signatories.

Photo Credits
Header Image: “Small Boy” nuclear test at the Nevada Test Site. Source: Department of Energy via WikiMedia Commons.
Question 1: Prime Minister Jawaharlal Nehru of India, Source: Wikimedia Commons; President John F Kennedy signing the Partial Nuclear Test Ban Treaty, Source: National Archives and Records Administration via Wikimedia Commons; Richard Nixon and Leonid Brezhnev, Source: National Archives and Records Administration