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Introducing Certification of Technical Necessity for Resumption of Nuclear Explosive Testing

10.25.24 | 5 min read | Text by Allie Maloney

The United States currently observes a voluntary moratorium on explosive nuclear weapons testing. At the same time, the National Nuclear Security Administration (NNSA) is required by law to maintain the capability to conduct an underground nuclear explosive test at the Nevada National Security Site, if directed to do so by the U.S. president. 

Restarting U.S. nuclear weapons testing could have very negative security implications for the United States unless it was determined to be an absolute technical or security necessity. A restart of U.S. nuclear testing for any reason could open the door for China, Russia, Pakistan, and India to do the same, and make it even harder to condemn North Korea for its testing program. This would have significant security consequences for the United States and global environmental impacts.

The United States conducted over 1,000 nuclear weapons tests before the 1991 testing moratorium took effect. It was able to do so with the world’s most advanced diagnostic and data detection equipment, which enabled the US to conduct advanced computer simulations after the end of testing. Neither Russia or China conducted as many tests, and many fewer of those were able to collect advanced metrics, hampering these countries’ ability to match American simulation capabilities. Enabling Russia and China to resume testing could narrow the technical advantage the United States has held in testing data since the testing moratorium went into effect in 1992. 

Aside from the security loss, nuclear testing would also have long-lasting radiological effects at the test site itself, including radiation contamination in the soil and groundwater, and the chance of venting into the atmosphere. Despite these downsides, a future president has the legal authority—for political or other reasons—to order a resumption of nuclear testing. Ensuring any such decision is more democratic and subject to a broader system of political accountability could be achieved by creating a more integrated approval process, based on scientific or security needs. To this end, Congress should pass legislation requiring the NNSA administrator to certify that an explosive nuclear test is technically necessary to rectify an existing problem or doubt in U.S. nuclear surety before a test can be conducted.

Challenges and Opportunities

The United States is party to the 1963 Limited Test Ban Treaty, which prohibits atmospheric tests, and the Threshold Ban Treaty of 1974, limiting underground tests of more than 150 kilotons of explosive yield. In 1992, the United States also established a legal moratorium on nuclear testing through the Hatfield-Exon-Mitchell Amendment, passed during the George H.W. Bush Administration. After extending this moratorium in 1993, the United States, Russia, and China also signed the Comprehensive Nuclear Test Ban Treaty (CTBT) in 1996, which prohibits nuclear explosions. However, none of the Annex 2 (nuclear armed) states have ratified the CTBT, which prevents it from entering into force. 

Since halting nuclear explosive tests in 1992, the United States has benefited from a comparative advantage over other nuclear-armed states, given its advanced simulation and computing technologies, coupled with extensive data collected from conducting over 1,000 explosive nuclear tests over nearly five decades. The NNSA’s Stockpile Stewardship Program uses computer simulations to combine new scientific research with data from past nuclear explosive tests to assess the reliability, safety, and security of the U.S. stockpile without returning to nuclear explosive testing. Congress has mandated that the NNSA must provide a yearly report to the Nuclear Weapons Council, which reports to the president on the reliability of the nuclear weapons stockpile. The NNSA also maintains the capability to test nuclear weapons at the Nevada Test Site as directed by President Clinton in Presidential Decision Directive 15 (PDD-15). National Security Memorandum 7 requires the NNSA to have the capability to conduct an underground explosive test with limited diagnostics within 36 months, but the NNSA has asserted in their Stockpile Stewardship and Management plan that domestic and international laws and regulations could slow down this timeline. A 2011 report to Congress from the Department of Energy stated that a small test for political reasons could take only 6–10 months.

For the past 27 years, the NNSA administrator and the three directors of the national laboratories have annually certified—following a lengthy assessment process—that “there is no technical reason to conduct nuclear explosive testing.” Now, some figures, including former President Trump’s National Security Advisor, have called for a resumption of U.S. nuclear testing for political reasons. Specifically, testing advocates suggest—despite a lack of technical justification—that a return to testing is necessary in order to maintain the reliability of the U.S. nuclear stockpile and to intimidate China and other adversaries at the bargaining table. 

A 2003 study by Sandia National Laboratories found that conducting an underground nuclear test would cost between $76 million and $84 million in then-year dollars, approximately $132 million to $146 million today. In addition to financial cost, explosive nuclear testing could also be costly to both humans and the environment even if conducted underground. For example, at least 32 underground tests performed at the Nevada Test Site were found to have released considerable quantities of radionuclides into the atmosphere through venting. Underground testing can also lead to contamination of land and groundwater. One of the most significant impacts of nuclear testing in the United States is the disproportionately high rate of thyroid cancer in Nevada and surrounding states due to radioactive contamination of the environment.

In addition to health and environmental concerns, the resumption of nuclear tests in the United States would likely trigger nuclear testing by other states—all of which would have comparatively more to gain and learn from testing. When the CTBT was signed, the United States had already conducted far more nuclear tests than China or Russia with better technology to collect data, including fiber optic cables and supercomputers. A return to nuclear testing would also weaken international norms on nonproliferation and, rather than coerce adversaries into a preferred course of action, likely instigate more aggressive behavior and heightened tensions in response.

Plan of Action

In order to ensure that, if resumed, explosive nuclear testing is done for technical rather than political reasons, Congress should amend existing legislation to implement checks and balances on the president’s ability to order such a resumption. Per section 2530 of title 50 of the United States Code, “No underground test of nuclear weapons may be conducted by the United States after September 30, 1996, unless a foreign state conducts a nuclear test after this date, at which time the prohibition on United States nuclear testing is lifted.” Congress should amend this legislation to stipulate that, prior to any nuclear test being conducted, the NNSA administrator must first certify that the objectives of the test cannot be achieved through simulation and are important enough to warrant an end to the moratorium. A new certification should be required for every individual test, and the amendment should require that the certification be provided in the form of a publicly available, unclassified report to Congress, in addition to a classified report. In the absence of such an amendment, the president should make a Presidential Decision Directive to call for a certification by the NNSA administrator and a public hearing under oath to certify the same results cannot be achieved through scientific simulation in order for a nuclear test to be conducted.

Conclusion

The United States should continue its voluntary moratorium on all types of explosive nuclear weapons tests and implement further checks on the president’s ability to call for a resumption of nuclear testing.

This action-ready policy memo is part of Day One 2025 — our effort to bring forward bold policy ideas, grounded in science and evidence, that can tackle the country’s biggest challenges and bring us closer to the prosperous, equitable and safe future that we all hope for whoever takes office in 2025 and beyond.