The Comprehensive Test Ban Treaty: Issues and Answers

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The Comprehensive Test Ban Treaty:
Issues and Answers

Matthew McKinzie

Peace Studies Program, Cornell University
Occasional Papers #21
June, 1997

Table of Contents

PREFACE

EXECUTIVE SUMMARY

Matthew McKinzie

REMARKS ON THE COMPREHENSIVE TEST BAN TREATY AND NUCLEAR NON-PROLIFERATION
THE COMPREHENSIVE TEST BAN TREATY FROM A GLOBAL PERSPECTIVE
THE COMPREHENSIVE NUCLEAR TEST-BAN TREATY: THE UNITED STATES PERSPECTIVE
IMPLICATIONS OF THE COMPREHENSIVE TEST BAN TREATY FOR THE UNITED STATES STOCKPILE STEWARDSHIP AND MANAGEMENT PROGRAM
THE COMPREHENSIVE TEST BAN TREATY IN THE CURRENT NUCLEAR CONTEXT
CAN A PROLIFERANT STATE ACQUIRE A NUCLEAR WEAPONS STOCKPILEWITHOUT TESTING?
SEISMOLOGICAL METHODS OF VERIFICATION AND THE INTERNATIONAL MONITORING SYSTEM
A SYSTEMS PERSPECTIVE OF COMPREHENSIVE TEST BAN TREATY MONITORING AND VERIFICATION
DEVELOPING DATABASES FOR MONITORING AND VERIFYING THE COMPREHENSIVE TEST BAN TREATY
SUMMING UP: QUESTIONS AND ANSWERS ON THE COMPREHENSIVE TEST BAN TREATY
Appendix I: Acronyms and Abbreviations
Appendix II: Author Biographies
Appendix III: Conference Participants

PREFACE

After decades of effort a Comprehensive Test Ban Treaty (CTBT) was finally approved by the United Nations General Assembly in October 1996. President Clinton, in signing the Treaty on behalf of the United States, called it "the longest-sought, hardest-fought prize in arms control." The Treaty prohibits all signatories from conducting any nuclear explosive test, or permitting such a test to be performed on territories under their control, and it establishes an international monitoring system to verify compliance. Any state party can request an on-site inspection in a member state to resolve compliance issues, and the Treaty empowers member states to act in concert against violators. It represents a significant -- perhaps the most significant -- step in the long process of building an international regime against the further proliferation of nuclear weapons or the development of new types of nuclear weapons.

For the treaty to enter in force, however, it must be ratified by a large number of named countries with nuclear capabilities (military or civil), including, of course, the United States. The U.S. Senate will be asked to give its consent to the CTBT, based on the treaty's expected impact on international security and U.S. national security. Much is at stake: ratification will bind the United States more tightly to the international nonproliferation regime, while failure to ratify would signal a significant weakening of that regime. The Senate will consider the effect of the treaty on nuclear proliferation and U.S. military capabilities, especially nuclear capability, and the potential for effective verification of treaty compliance. Its deliberations should be informed and supported by a public debate on these issues, a debate that can only occur if information on technical and political aspects of the treaty is widely available.

The Peace Studies Program of Cornell University sponsored a workshop in Ithaca on October 11-13, 1996 to discuss issues surrounding congressional ratification of the CTBT. The workshop was organized by Matthew McKinzie, with the help of Judith Reppy and the Advisory Council to the Peace Studies Program's Project on Technology and Security: Richard Garwin, Kurt Gottfried, Lisbeth Gronlund, George Lewis, Herbert Lin, Peter Stein, Jeremiah Sullivan, Zellman Warhaft, and David Wright. Participants in the workshop came from a variety of backgrounds, including the U.S. Arms Control and Disarmament Agency, the Department of Energy, the Department of Defense, the Central Intelligence Agency, non-governmental organizations, and universities. A list of workshop participants and their affiliations can be found in Appendix 3. Commissioned papers discussed the political context for the treaty, the technical challenges and capabilities relevant to the verification regime, and the impact of the treaty on nuclear proliferation and international security. These papers have been revised in light of the discussion at the workshop and are reproduced in this Peace Studies Occasional Paper, along with an Executive Summary and several appendices. It is our hope that they will provide a useful and accessible source of information to the public debate on treaty ratification.

We wish to thank all the participants for their thoughtful contributions to the workshop discussion. Elaine Scott and Sandra Kisner of the Peace Studies Program staff provided the essential administrative support with their usual efficiency and good humor; it is no exaggeration to say that without their help the Program could not function. Funding for the workshop came from the John D. and Catherine T. MacArthur Foundation's institutional training grant to the Peace Studies Program.

EXECUTIVE SUMMARY
Matthew McKinzie
Peace Studies Program, Cornell University

Background

On 24 September 1996 President Clinton signed the Comprehensive Test Ban Treaty (CTBT) during a ceremony at the United Nations, describing this achievement as "the longest-sought, hardest-fought prize in arms control." As of May 1997, more than three-quarters of the world's states have signed the Comprehensive Test Ban, including the other four declared nuclear powers: Russia, China, France, and the United Kingdom. The United States is one of the 44 states that must ratify the CTBT before it may enter into force. This collection of papers has been published to inform Senate decision-making on advice and consent to ratify the Comprehensive Test Ban Treaty.

The Comprehensive Test Ban Treaty establishes a universal norm against nuclear testing and an effective means to monitor compliance, and it aligns the nuclear powers with the vast majority of non-nuclear weapon states against proliferation. More specifically, it prohibits states capabilities relevant to the verification regime, and the impact of thfrom conducting any nuclear explosive test, or permitting such a test to be performed on territories under their control. The CTBT establishes an international monitoring system to monitor all terrestrial testing environments globally and in near-real time for evidence of a nuclear explosion. Any state party can request an on-site inspection in a member state to resolve compliance issues based on data produced from this monitoring system, supplemented by intelligence derived from the national technical means of states parties. In conformity with international law, the Comprehensive Test Ban empowers member states to act in concert against Treaty violators.

By strengthening the nuclear non-proliferation regime and arresting the development of new types of weapons by the other nuclear powers, the CTBT strengthens U.S. national security. The Comprehensive Test Ban accomplishes these U.S. objectives verifiably. Through the Department of Energy Stockpile Stewardship and Management Program, the benefits of the CTBT are compatible with the U.S. objective of maintaining the safety and reliability of the enduring U.S. nuclear deterrent.

Achieving U.S. Non-proliferation and Arms Control Objectives

The demise of the Soviet Union and substantial reductions in Cold War arsenals have shifted attention to the security threats posed by proliferation of nuclear weapons. Three U.S. objectives were achieved by the successful negotiation of the CTBT: a further barrier to horizontal proliferation is now in place; high confidence in the deployment of new types of nuclear weapons by the recognized nuclear weapon states is now very difficult, if not impossible; and the regime of legally binding treaty constraints is strengthened.

A nuclear explosive test is the most important experiment in the development of nuclear weapons. A single test can confirm impressive gains in capabilities; even a few tests are of considerable value to a proliferant state. The ability of additional states to acquire nuclear weapons is increasing with the enormous expansion in the number of individuals able to access computers and model complex physical systems; with the spread of nuclear reactors for research and the production of electric power; and with the accumulation of plutonium and highly-enriched uranium from spent reactor fuel and disassembled weapons. By ending nuclear testing, the Comprehensive Test Ban Treaty creates a significant obstacle to the confident acquisition of nuclear weapons. Without the possibility of testing, the nuclear weapon design choices for a proliferant state are limited to a configuration in which performance uncertainties would be minimized, i.e., crude fission weapons similar to the original U.S. designs of more than 50 years ago. Acquisition of thermonuclear weapons is thereby denied. Confident deployment of boosted fission weapons designs that conserve fissile material and permit enhanced yield-to-weight ratios is also heavily compromised. Without explosive testing, high confidence in even crude fission weapons is not attainable, thus planting critical reservations in the minds of potential military users.

The Comprehensive Test Ban Treaty is a significant disarmament measure. It enhances deterrent stability as the United States and Russia reduce their nuclear capabilities unilaterally and in accordance with the Intermediate-Range Nuclear Forces Treaty and the Strategic Arms Reduction Treaties. The "zero-yield" scope of the CTBT blocks development of new weapons by Russia, China, France, the United Kingdom, and the United States across the full spectrum of use: tactical, theater, and strategic. Confidence in significant modifications to existing weapon designs is critically dependent on the ability to confirm such modifications through testing. The decision of the nuclear powers to sign the CTBT represents their judgment that global security, and their own national interests, are better served by foregoing further options to develop and field new types of nuclear weapons.

The nuclear non-proliferation regime of legally binding treaty constraints and export controls, of which the Nuclear Non-Proliferation Treaty (NPT) is the foundation, remains a crucial factor holding in check the further spread of nuclear weapons. Failure to negotiate a CTBT would have risked unraveling this regime, as the achievement of a comprehensive test ban has been a central tenet of the NPT since its inception. For the non-nuclear weapon states the CTBT is a gauge of progress in nuclear disarmament, a quid-pro-quo for giving up their sovereign right to develop nuclear weapons. For the United States the political benefits of the CTBT are enormous: it aligns the nuclear powers with the vast majority of non-nuclear weapon states, allowing the United States to assume a leadership role against any proliferant state. Such a state clearly risks sanctions and more severe international response in the face of the now strengthened non-proliferation regime.

Maintaining the U.S. Nuclear Deterrent

The nuclear arsenal of the United States is currently safe and reliable. The U.S. Department of Energy Stockpile Stewardship and Management Program (SSMP) represents an integrated set of capabilities designed to produce high confidence in the future safety and reliability of the U.S. nuclear weapons stockpile without nuclear testing or stockpile modernization. Under the U.S. test moratorium in place since 1993, future confidence in the safety and reliability of U.S. nuclear weapons is being based on the legacy of past testing, enhanced stockpile monitoring and assessment, and on the capability to remanufacture weapons as needed, buttressed by improvements in predictive weapons science. A successful SSMP makes the continued reliance of the United States on nuclear deterrence for its security compatible with ratification of the Comprehensive Test Ban Treaty. The general reasons supporting this conclusion are primarily technical, but also concern the present security environment.

Technically, an SSMP has the potential to succeed today based on improvements in computer technology that are critical to further achievements in modeling and on evidence that weapons scientists and engineers can simulate some nuclear weapons phenomena in hydrodynamic and high-energy-density facilities. Politically, the international security environment in the present and likely future allows the United States to depend on its existing types of nuclear weapons. Should the security environment deteriorate so that new types of nuclear weapons are required, or should unforseen problems arise in the enduring nuclear arsenal which require testing to repair, the United States has emphasized its freedom to withdraw from the CTBT under the "supreme national interest" clause within six months of stating its intent to do so.

Monitoring the Comprehensive Test Ban Treaty

During the negotiating process for the Comprehensive Test Ban Treaty, the United States sought and achieved a monitoring regime that will provide effective verification. The CTBT International Monitoring System (IMS), combined with the national technical means of states parties, will insure that significant nuclear explosive tests conducted in violation of the Treaty will be detected, identified, and attributable to a source. The basic U.S. monitoring criteria is that a nuclear test with a yield of "a few kilotons, evasively tested" will be detected with high confidence. With coordinated effort between specialists who have worked on test ban monitoring and specialists who have worked on earthquake monitoring, the IMS will be able to meet these U.S. monitoring goals.

The IMS approach to monitoring the CTBT uses the strategy of roughly homogeneous global coverage. Monitoring stations of the international regime will continuously sample potential testing environments: seismic monitoring for the detection of underground tests, hydroacoustic monitoring for undersea tests, infrasound monitoring for atmospheric tests, and radionuclide monitoring to obtain trace evidence of a nuclear explosion releasing radioactivity into the atmosphere. Data produced from these monitoring stations will be relayed to the CTBT International Data Center, processed, and released to CTBT states parties. The CTBT provides for confidence-building measures and consultation and clarification procedures to aid in the diplomatic resolution of a problematic event, in addition to the possibility of seeking an on-site inspection. The permitted use of data derived from National Technical Means (NTM) to request an on-site inspection represents a monitoring strategy complementary to the global IMS coverage, one in which the United States can direct its national intelligence assets to regions of concern. The IMS and NTM taken as a whole present a formidable challenge to would-be evaders.

Entry Into Force

The Comprehensive Test Ban Treaty text specifically names 44 states now possessing significant civilian and/or military nuclear capabilities that must ratify the treaty before it can enter into force. Of these 44 states, India, Pakistan and North Korea have not signed the CTBT as of May 1997. India strongly opposed the final text of the CTBT during the close of the negotiations, and sought to block its transmission to the United Nations General Assembly. The past year has seen three Indian governments: Inder Kumar Gujral, the current Prime Minister, was Foreign Minister during the Test Ban negotiations and a proponent of India's opposition to the CTBT. Pakistan's stated policy is not to sign the CTBT unless India does.

If the Comprehensive Test Ban Treaty has not entered into force by 24 September 1999, a majority of those states that have by then ratified the CTBT may convene a Conference of States. Under Article XIV, ¶2 of the Comprehensive Test Ban Treaty, this Conference "shall consider and decide by consensus what measures consistent with international law may be undertaken to accelerate the ratification process in order to facilitate the early entry into force of this Treaty."

Conclusions

Over the past 51 years, a total of 2,046 explosive nuclear tests were conducted by the United States, the Soviet Union, the United Kingdom, France, China, and India, releasing the energy equivalent of over one-half billion tons of chemical high explosives; during this period a nuclear test occurred on average once every nine days. The end of the Cold War brought about fundamental, positive changes in the global security environment in accord with principal foreign policy objectives long sought by the United States. These changes are reflected in the record of nuclear testing since the disintegration of the Soviet Union: a consensus among the nuclear powers at the close of the 20th century has ended the era of nuclear explosive testing begun during the second World War. A verifiable treaty banning all explosive testing of nuclear weapons, universally in force, will cement this hard-won consensus, preserving it and strengthening it as the world community of states strives for a more peaceful future. Ratification by the United States is essential for the momentum of the Comprehensive Test Ban Treaty to continue to entry-into-force, an outcome that now and in the future will increase U.S. national security.