U.S. Nuclear Weapons Tests

This document from the Congressional Research Service (CRS) provides information on U.S. nuclear weapons tests. It explains that the United States has maintained a voluntary moratorium on nuclear explosive testing since 1992, although it retains the capability to resume testing if necessary. The document discusses the limits on U.S. nuclear tests, including the temporary moratorium established by Congress in 1992 and the United States' commitments under international treaties such as the Limited Test Ban Treaty and the Threshold Test Ban Treaty.

The document also addresses the Comprehensive Test Ban Treaty (CTBT), which aims to ban all nuclear explosions. While the United States signed the treaty in 1996, the Senate rejected its ratification in 1999. As of March 2020, the CTBT has been signed by 184 states and ratified by 168, but it has not entered into force. The United States has indicated that it will continue to observe its unilateral moratorium on nuclear testing. The document mentions concerns raised by the U.S. State Department regarding Russia and China's compliance with the CTBT's zero-yield standard, although experts have questioned the assertions made.

The document explains the Science-Based Stockpile Stewardship program, which the United States has employed since 1993 to maintain the safety, security, and effectiveness of its nuclear arsenal without explosive testing. It outlines the capabilities and activities of the National Nuclear Security Administration (NNSA) in maintaining stockpile readiness, including subcritical experiments conducted at the Nevada National Security Site.

Regarding U.S. test readiness, the document notes that the United States could resume underground explosive testing within 24-36 months of a decision to do so. It discusses the regulatory requirements, compliance with international treaties, and potential response times associated with resuming testing. The document highlights that the NNSA has not allocated separate funding for maintaining test readiness since 2010 and that the cost and specific details of conducting a nuclear test would vary.

The document mentions the potential international implications of a U.S. decision to conduct a nuclear test. It discusses arguments both for and against testing, with some suggesting it could be used as a negotiating tool, while others warn of negative consequences for arms control and nonproliferation efforts.