Analysis of U.S. Nuclear Weapons Testing Policies and Their Impacts

Key Chapter Title List

1. Current Status of U.S. Nuclear Weapons Testing and the Voluntary Moratorium
2. Restrictions on U.S. Nuclear Testing
3. The Comprehensive Nuclear-Test-Ban Treaty (CTBT) and the U.S. Position
4. Foreign Nuclear Testing Activities and Compliance Status
5. Science-Based Stockpile Stewardship Program and Subcritical Experiments
6. U.S. Test Readiness and Timeline
7. Potential Impacts and Policy Debate on Resuming Nuclear Testing
8. Disclaimer

Document Introduction

This report, based on professional analysis from the Congressional Research Service (CRS), systematically examines U.S. nuclear weapons testing policy since the implementation of the voluntary moratorium on explosive nuclear testing in 1992, alternative technical pathways for maintaining the reliability of the nuclear arsenal, and the ongoing strategic debate surrounding whether testing should be resumed. Focusing on multidimensional factors including domestic legal frameworks, international treaty obligations, technical readiness, and geopolitical interactions, the report provides an authoritative perspective for understanding the evolution and current challenges of U.S. nuclear deterrence policy.

The report first outlines the voluntary moratorium status adhered to by the United States since 1992, although it retains the capability to resume testing at the Nevada National Security Site (NNSS). The core alternative is the Science-Based Stockpile Stewardship Program implemented since 1993, which aims to ensure the safety, security, and effectiveness of the nuclear stockpile through computational simulations, subcritical experiments, and other non-explosive means. The report mentions discussions among Trump administration officials in 2020 regarding conducting a nuclear test but notes that subsequent administrations have reaffirmed the moratorium position.

In the section on legal and treaty frameworks, the report details the multiple layers restricting U.S. nuclear testing: including the 1963 Partial Test Ban Treaty (prohibiting atmospheric, outer space, and underwater tests), the 1974 Threshold Test Ban Treaty (prohibiting underground tests exceeding 150 kilotons), and the 1992 Hatfield-Exon-Mitchell Amendment with domestic legal effect. This amendment mandates a moratorium on underground nuclear testing but includes a reciprocity clause allowing the U.S. to resume testing if another state conducts a test. The report also provides an in-depth analysis of the status of the Comprehensive Nuclear-Test-Ban Treaty (CTBT), noting that while the U.S. has signed it, the treaty has not been ratified and has not entered into force due to non-ratification by specific states. The report pays particular attention to Russia's withdrawal of its ratification in 2023 and the U.S. government's ongoing concerns regarding compliance with the zero-yield standard by China and Russia.

At the technical and management level, the report explains the specific measures taken by the National Nuclear Security Administration (NNSA) to maintain readiness through the Stockpile Stewardship Program, including the development of the annual Stockpile Stewardship and Management Plan (SSMP), and maintaining preparedness to conduct underground nuclear explosive tests if necessary. According to policy settings, the U.S. aims to resume testing within 24-36 months of a presidential decision, but the actual timeline is significantly influenced by compliance with environmental, health, and safety regulations, which the President can waive under a national emergency.

Finally, the report comprehensively assesses the broad strategic impacts that resuming nuclear testing could trigger. Proponents argue that testing could be used for negotiation leverage or to maintain a technical advantage over China and Russia; opponents warn that it could stimulate adversaries to restart testing, trigger an arms race, damage the nuclear non-proliferation regime, and pose risks to the environment and public health in Nevada. These debates highlight the fundamental policy trade-offs between maintaining nuclear deterrence reliability, adhering to international norms, and managing potential escalation risks.

The information contained in this report is derived from original analysis provided by CRS to Congress. The content is professional and objective, offering indispensable in-depth reference for defense policy researchers, arms control analysts, and geopolitical observers.