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The International Security Value of the Nuclear Test Ban Treaty

Category and Description

Nuclear Testing
Brief, November 2002

Press Contacts: Daryl Kimball, Executive Director (202) 463-8270 x107

A global halt to nuclear weapons test explosions has been a key security objective for the international community since it was first proposed by Indian Prime Minister Jawaharlal Nehru in April 1954 and negotiations between U.S. President Dwight D. Eisenhower and Soviet Premier Nikita Khrushchev were initiated in 1958. Although subsequent U.S.-U.K.-Soviet negotiations led to the 1963 Limited Test Ban Treaty prohibiting atmospheric testing, the nuclear powers failed to reach agreement on a comprehensive ban. For the next 25 years, France, China, and India developed and tested nuclear weapons, while underground U.S. and Soviet nuclear testing continued to allow the introduction of new nuclear weapons. Spurred by nuclear testing moratoria enacted by Russia, France, and the United States, and strong civil society support in the early 1990s, multilateral negotiations on the Comprehensive Test Ban Treaty (CTBT) were concluded in August 1996, and the treaty was opened for signature at the United Nations September 24, 1996.

Fifty years of progress, setbacks, and political debate produced the treaty, which “prohibits any nuclear weapon test explosion or any other nuclear explosion” and aims to constrain the qualitative improvement of nuclear weapons, curb proliferation, and advance disarmament. By the end of October 2002, 166 countries had signed the treaty, including 41 of the 44 states required for entry into force. Nevertheless, six years after opening for signature, the CTBT is in jeopardy. Thirteen key states—including China, India, Israel, Pakistan, and the United States—must sign and/or ratify to enable the accord to take full legal effect. With each year that passes without the CTBT’s entry into force, the odds increase that one state or another will resume nuclear testing.

Six years ago, UN member states overwhelmingly endorsed the CTBT in a 158-3 vote. Today, international support remains strong. Unfortunately, the CTBT’s full implementation has become sidetracked by political posturing, particularly in the United States, India, and Pakistan. Consequently, it is especially important to recall the purpose of the CTBT, recognize the challenges to its entry into force, and consider the consequences for national and international security if nuclear testing resumed.

Why Pursue Entry Into Force?

The implementation of the CTBT will contribute in a host of ways to advancing global nuclear nonproliferation and disarmament, as well as preventing further environmental damage from testing. The treaty’s primary role would be to curb the development and creation of new nuclear weapons. Nuclear testing is necessary for the development of sophisticated, new types of nuclear warheads. Although crude nuclear devices can be produced without testing, a new nuclear warhead small enough to be delivered by missiles would require nuclear test explosions to certify its integrity.

By impeding the development of advanced, new types of nuclear warheads, the treaty would reduce dangerous nuclear arms competition between the existing nuclear-capable states. Test ban treaty signature and ratification by India and Pakistan would not eliminate their existing nuclear capabilities; however, it would rule out further development and operational deployment of new thermonuclear weapons that could be delivered on longer-range systems, thus dampening a destabilizing arms race in the region. China would be restrained from testing more advanced nuclear warhead designs that would enable it to field multiple-warhead ballistic missiles.

Far-reaching nuclear test monitoring provisions under the CTBT, including an international monitoring network, intrusive on-site inspections on short notice, and confidence-building measures, will help ensure global compliance with the test ban. The full-scale implementation of this system depends on the treaty’s entry into force. While some countries possess powerful national intelligence capabilities that bolster the CTBT’s monitoring and verification system, most do not. By combining technical and intelligence resources so that states can probe questionable activities and deter potential treaty violations, the treaty’s integrated system provides added confidence and transparency.

Entry into force of the CTBT would also prevent additional environmental and health damage from nuclear test explosions. Since 1945, seven countries have conducted 2,050 nuclear test explosions. Most of these tests were conducted at U.S. test sites in Nevada and the Marshall Islands, the Soviet Union’s test sites in Kazakhstan and Novaya Zemlya, France’s test site on the Polynesian atolls of Fangataufa and Moruroa, China’s Lop Nor test site, and in Algeria and Australia. Most of the tests were conducted in the lands of indigenous peoples and far from the capitals of the testing governments. The 528 atmospheric tests delivered radioactive materials that produced approximately 430,000 additional cancer fatalities by the year 2000, according to a 1990 report by the International Physicians for the Prevention of Nuclear War. The U.S. National Cancer Institute estimated in a 1997 report that the 90 dirtiest U.S. tests could cause 7,500-75,000 additional cases of thyroid cancer.

While underground nuclear blasts pose a much smaller radioactive hazard than atmospheric tests, there has been widespread venting from underground explosions, especially at the Semipalatinsk test site in Kazakhstan. The United States has acknowledged that 114 of its 723 underground tests released radioactive material into the atmosphere. In addition, underground nuclear blasts leave a legacy of radioactive contamination, which eventually might leak into the surrounding environment.

Treaties, Norms, and Security

The CTBT does not stand or fall by itself; rather, it is an essential part of a network of treaties, agreements, and norms that underpin international efforts to prevent the spread of weapons of mass destruction and codify bilateral and multilateral arms control and disarmament agreements. Repudiating or weakening one or more elements erodes the overall framework. At the heart of the network is the nuclear Nonproliferation Treaty (NPT), which entered into force in 1970 and now has 187 member states. The nuclear-weapon states promised in Article VI of the NPT to pursue good-faith negotiations on measures relating to nuclear disarmament. All but two of the non-nuclear NPT member states have fully complied with their obligations, and they view the CTBT as a long-overdue element of the nuclear-weapon states’ disarmament commitment.

The NPT was extended indefinitely in 1995 largely on the basis of the renewed commitment by the major nuclear weapons powers to complete the CTBT and pursue other Article VI objectives. The “importance and urgency of signatures and ratifications, without delay and without conditions to achieve the early entry into force of the Comprehensive Nuclear Test Ban Treaty” was reaffirmed at the 2000 NPT Review Conference.

To reinforce the CTBT’s importance in the nonproliferation framework, 18 foreign ministers issued a statement at the United Nations in September 2002. Reaffirming the hope for a treaty that “would contribute to systematic and progressive reduction of nuclear weapons…as a major instrument in the field of nuclear disarmament and nonproliferation,” they called on all states who are holding out on signing and/or ratifying to do so to ensure the treaty’s timely entry into force. They cited the CTBT’s importance in preventing the proliferation of nuclear materials and know-how, and expressed concern over the international tensions that have prevailed since the treaty’s negotiation. To date, the document has been endorsed by 50 governments.

Danger Signs

Several international political developments have put obstacles in the path of the CTBT since it opened for signature in 1996. The repercussions of increased talk of nuclear testing are grim: if just one country resumes testing for new nuclear designs or other purposes, the door would open for the resumption of nuclear testing by other countries and the renewal of the nuclear arms race.

United States: The United States, which had played a leadership role in negotiating the CTBT, is now one of the major hold-out states. On October 13, 1999, the Senate became the first and only legislature to reject ratification, despite support from military leaders such as General Colin Powell and public opinion polls showing that 82 percent of all Americans backed the treaty. Since taking office, President George W. Bush’s administration has indicated that the White House will not ask the Senate to reconsider approval of the CTBT, but it has pledged to maintain the decade-old testing moratorium for now. The CTBT cannot win Senate approval for ratification without presidential support, but the president also cannot unilaterally withdraw the treaty from the Senate’s consideration. Thus, the CTBT is trapped in U.S. political limbo.

Meanwhile, the Bush administration continues to take actions that undermine the CTBT. In August 2001, Washington announced that it would not fund the development of international on-site inspections capabilities, a critical component to the treaty’s verification regime. During the UN General Assembly in November 2001, the United States voted against an annual resolution that would place the CTBT on the meeting’s agenda; later that month, the Bush administration refused to send a representative to the CTBT’s Article XIV Entry into Force Conference, stating, “We’re just not going to engage.”

The Bush administration’s policy choices are driven by an apparent desire to keep all options open to develop new types of nuclear weapons. The administration’s January 2002 Nuclear Posture Review (NPR) cites the potential need for new nuclear weapons capabilities to defeat hardened and deeply buried targets, such as facilities that might be used for producing biological or chemical weapons. While U.S. conventional capabilities are robust, the Pentagon seeks more powerful means to destroy the targets. Noting that the current moratorium “may not be possible for the indefinite future,” the NPR leaves open the possibility for additional nuclear test explosions to provide military confidence in developing and fielding new types of nuclear warheads. The NPR also states that a new generation of nuclear weapons will debut in the U.S. nuclear arsenal beginning in 2020. New warheads for updated sea- and land-launched ballistic missiles could give Washington a reason to resume nuclear testing.

As a first step toward realizing these grander ambitions, the administration contends that nuclear test explosions might be needed to maintain existing U.S. nuclear weapons. In August 2002, Dale Klein, director of the president’s top nuclear weapons advisory council, told reporters on a visit to the Nevada Test Site that “as time goes on there will likely have to be some tests performed beyond the small scale” to address possible aging problems in the nuclear stockpile. In anticipation of renewed testing, the White House asked Congress to authorize $15 million in the fiscal 2003 budget to shorten the timeline for test preparation—presently 24-36 months.

However, the “need” to resume nuclear testing has been strongly rebutted by independent military and scientific experts. Former Chairman of the Joint Chiefs of Staff General John Shalikashvili noted in his January 2001 report, “The nation’s arsenal is safe, reliable and able to meet all stated military requirements...for as far into the future as we can see.” A National Academy of Sciences panel, which included three former nuclear laboratory directors, confirmed in a July 2002 report that the United States “has the technical capabilities to maintain confidence in the safety and reliability of its existing nuclear-weapon stockpile under [a test ban], provided that adequate resources are made available to the Department of Energy’s nuclear-weapon complex and are properly focused on this task.” While the study noted that age-related defects in mainly non-nuclear components can be expected, “no need was ever identified for a program that would periodically subject stockpile weapons to nuclear tests.” Currently, the United States spends over $5 billion each year on its Stockpile Stewardship Program for nuclear weapons maintenance, non-nuclear and subcritical nuclear testing, research and development, and even some limited modifications of the U.S. arsenal.

China: In response to the threatened deployment of an extensive U.S. national missile defense system, Beijing might seek to resume testing in order to develop more sophisticated strategic nuclear missiles armed with multiple warheads. U.S. intelligence reports estimated as recently as July 2002 that China might build up its strategic arsenal in the coming decade from 20 missiles to 75-100 in response to a U.S. national missile defense deployment. China, like the United States, has signed the CTBT but has so far failed to take action to ratify the treaty.

Russia: Like the United States and China, Russia continues to conduct subcritical testing and remains capable of resuming full-scale testing and developing new weapons for deployment if the CTBT should fail. However, several positive steps have shown Moscow’s interest in bringing the treaty into force. The Russian Duma approved CTBT ratification in April 2000, and the Kremlin has called upon other states to sign or ratify. Russian Defense Minister Igor Sergeyev proposed in November 2001 that Russia might consider “additional verification measures for nuclear test ranges going far beyond the treaty provisions,” but only after the treaty enters into force.

India and Pakistan: The May 1998 nuclear blasts by India and Pakistan not only set back the drive for the CTBT but also made its value even more obvious. The two states have refused to sign the CTBT because they are concerned that the test ban would cap their nuclear ambitions. Both governments are under pressure from their nuclear laboratories to conduct further tests, and lack of progress on nuclear restraint measures in South Asia could increase political pressure in India and Pakistan to conduct further test explosions to perfect new types of warheads, including two-stage thermonuclear weapons. Both are also aware, however, of the strength of international opinion supporting the norm that the CTBT has begun to establish against testing. The two countries declared voluntary moratoria on testing shortly after the May 1998 tests, but each country indicated that they are awaiting the other’s signature before signing the CTBT themselves.

Preventing Treaty Violations

The treaty’s negotiators, who included scientists from many countries with expertise in a number of relevant fields, created a comprehensive verification system designed to detect and identify any militarily significant nuclear explosions with a high level of confidence. The verification system, which is to be administered by the Vienna-based CTBT Organization (CTBTO), includes the International Monitoring System (IMS), the International Data Centre, and the On-Site Inspection regime.

The IMS is comprised of 321 monitoring stations worldwide with sensors that can detect possible nuclear explosions using four technologies—seismic, hydroacoustic, radionuclide, and infrasound. The International Data Centre collects information from IMS activities and disseminates the data to member states for feedback. These capabilities can be augmented with additional information from members’ own national technical means, as well as commercial satellites and thousands of civilian seismic monitoring stations. In the event of a suspected nuclear explosion, states may request inspection of an alleged violator under the On-Site Inspection regime.

The key to effective verification is that a potential violator must believe that the risk of being caught is greater than the benefit of the violation. Conversely, the verifier must be convinced that the security benefits of identifying (and thus deterring) tests of substantial yield exceeds the military threat posed by any small test that might escape detection. A major argument leveled against the CTBT by its opponents is that very low-yield nuclear explosions cannot be verified with absolute certainty. However, this argument misses the point on verification and implies that low-yield tests are militarily significant. Explosions below a few hundred tons—potentially at a low enough yield to evade detection—are not useful in assessing a nuclear weapon’s design.

Leading experts and successive studies, including the July 2002 National Academy of Sciences study, have determined that no would-be violator could have confidence that a nuclear explosion of any military utility would escape detection. If funding continues and the program is fully established, the CTBT verification regime is more than equal to the task. If cheating was discovered, the CTBT allows states-parties to pursue strong measures to deal with noncompliance and to reduce nuclear dangers.

While member states work to bring the treaty into force, maintaining the commitment to further develop the CTBTO Preparatory Commission is important. The CTBTO has an annual budget of approximately $85 million to establish a system of global monitoring, data analysis, and on-site inspections. If implementation is indefinitely delayed, financial support for the establishment of the treaty’s monitoring and verification system might wane. Already, the Bush administration announced that while it will continue to support the CTBTO’s International Monitoring System, it is unwilling to help finance or participate in activities related to on-site inspections.

The Costs of Inaction

Further delay of the CTBT’s entry into force, particularly if the delay is permanent, could undermine adherence to other arms control agreements. The NPT and CTBT were linked when the nuclear-weapon states promised to act on the test ban treaty in exchange for the indefinite extension of the NPT; now, rejection of the CTBT by some states might provide an excuse for a government that wishes to renounce or thwart its NPT obligations. While widespread repudiation of the NPT is not likely in the immediate future, the regime is vulnerable due to stalled progress and political infighting on the CTBT. Although the CTBT alone cannot stop the spread and development of nuclear weapons, the world cannot effectively pursue nonproliferation and disarmament without it.

What would be the consequences of the CTBT not entering into force? There are two likely alternatives: no CTBT, but continued commitment to moratoria; or, resumption of nuclear testing by one or more countries. The first might look convenient, but in the absence of an enforceable verification regime like the CTBT, compliance problems would be difficult to resolve, thus increasing international tensions. Some form of provisional application or selective entry into force undertaken by those who had ratified the CTBT could go some way toward addressing the problems, but this would require the participation of all states that have conducted nuclear tests.

Measures to Support the CTBT

While it might be possible to sustain the unilateral moratoria undertaken by the nuclear testing states for several years, uncertainties and the risk of a resumption of testing will only grow over time. The norm against nuclear testing remained firm in the immediate aftermath of the 1998 South Asian nuclear tests, but President Bush’s criticism of the CTBT and speculation about the possible resumption of nuclear testing is damaging the credibility of that norm. Measures must be undertaken to uphold nuclear testing moratoria and secure the ratifications necessary for CTBT entry into force:

  • The international community should urge the 13 states preventing entry into force to sign or ratify the CTBT without conditions or reservations. States-parties to the CTBT should continue to work together systematically to send high-level groups of emissaries to key countries that have not yet signed or ratified the treaty in order to facilitate and encourage their support for the CTBT.
  • The leaders and the governments of the 13 CTBT hold-out states should reconsider and recommit themselves to the ratification of the CTBT. In the meantime, they should maintain their nuclear testing moratoria, fully support the work of the CTBTO Preparatory Commission, and announce that they will refrain from the pursuit of new types of nuclear weapons, which requires testing to validate the weapons’ integrity.
  • Each signatory should provide adequate financial, political, and technical support for the continued development and operation of the CTBTO so that the International Data Center, the International Monitoring System, and the executive secretariat are available and ready to monitor and verify compliance when the CTBT enters into force. States should also support the timely establishment of an effective verification system, open access to data, and the development of procedures for effective and timely on-site inspections.
  • Until the CTBT enters into force, the nuclear-weapon states with active test sites should voluntarily agree to periodic inspections of their test sites by observers on behalf of the CTBTO and signatory states to increase confidence that clandestine nuclear testing has not occurred. They should also agree to avoid activities at their test sites that might be mistaken for nuclear weapon test preparations, such as subcritical experiments.