Case for the CTBT Is Stronger Than Ever

Daryl G. Kimball

Preventing the spread and buildup of nuclear weapons remains one of the highest priority international security challenges. Success depends on a multipronged global strategy, including a verifiable ban on nuclear explosive testing to prevent the emergence of new and more deadly nuclear weapons. U.S. leadership is critical.

With its two-decade-long moratorium on testing and its 1996 signature on the Comprehensive Test Ban Treaty (CTBT), the United States already has assumed most CTBT-related responsibilities. The full security benefits of the treaty, however, depend on U.S. ratification, which would trigger ratification by other holdout states, including China, India, and Pakistan.

A new report by a panel of the National Academy of Sciences (NAS) on technical issues related to the CTBT reaffirms that the United States no longer needs and would not benefit from further nuclear testing. The study explains why the treaty would significantly improve U.S. capabilities to detect and deter nuclear test explosions by others.

The detailed report by the NAS panel of senior scientific and military experts documents the significant technical advances over the past decade that should resolve earlier concerns about the treaty. In the weeks and months ahead, senators and their staff need to take a serious look at the merits of the CTBT in light of the new NAS findings and not rush to judgment on the basis of old myths and misconceptions.

The study finds that maintaining an effective nuclear stockpile will require continued diligence, but it does not require nuclear test explosions. The panel finds that the National Nuclear Security Administration (NNSA) nuclear weapons Stockpile Stewardship Program “has been more successful than was anticipated in 1999,” when the Senate last considered the CTBT.

Just as the 2002 NAS report on the CTBT concluded, the new study finds that if sufficient resources are dedicated to the task, the United States has the technical ability to maintain a safe, secure, and reliable stockpile of nuclear weapons into the foreseeable future without nuclear explosive tests.

Today, the nuclear weapons laboratories have more resources and better tools than ever before. Since 2009, funding for the NNSA nuclear weapons complex has increased 13 percent, and the Obama administration’s $7.6 billion request for fiscal year 2013 would boost funding by another 5 percent.

As Sen. Dianne Feinstein (D-Calif.) noted at a recent Senate Appropriations subcommittee hearing, “Regarding nuclear weapons activities, I believe the fiscal year 2013 budget request provides more than sufficient funding to modernize the nuclear weapons stockpile.”

Another key conclusion of the NAS panel is that “the status of U.S. national monitoring and the International Monitoring System [IMS] has improved to levels better than predicted in 1999.” The new study documents advances in the capabilities of U.S. national technical means (NTM) and the IMS in all areas: seismic, hydroacoustic, infrasound, radionuclide, and satellite monitoring.

The new report also confirms that, with the combined capabilities of the nearly completed IMS and even more capable NTM, as well as tens of thousands of civilian seismic monitoring stations, no potential CTBT violator could be confident that a nuclear explosion of military utility would escape detection.

The panel’s report finds that “[c]onstraints placed on nuclear-explosion testing by the monitoring capabilities of the IMS and…U.S. NTM will reduce the likelihood of successful clandestine nuclear-explosion testing, and inhibit the development of new types of strategic nuclear weapons.” For example, the global test ban would make it far more difficult for China, India, and Pakistan to perfect the more-compact warhead designs that would allow them to field missiles armed with multiple warheads.

The report concludes that “[o]ther states intent on acquiring and deploying modern, two-stage thermonuclear weapons would not be able to have confidence in their performance without multi-kiloton testing. Such tests would likely be detectable (even with evasion measures).” In other words, without nuclear explosive testing, states such as Iran could not perfect sophisticated two-stage thermonuclear warheads that can be delivered on long-range ballistic missiles.

The panel notes that once the treaty enters into force, the possibility of short-notice, on-site challenge inspections “constitutes a deterrent to treaty violation whether or not an inspection actually takes place.” It finds that “the development of weapons with lower capabilities…is possible with or without the CTBT…but such developments would not require the United States to return to nuclear testing in order to respond.”

President Barack Obama has repeatedly expressed his support for U.S. ratification and prompt entry into force of the CTBT. But to realize the promise of the test ban, he must provide stronger leadership to create the necessary support for a successful Senate vote sometime in 2013.

With the CTBT, the United States stands to lose nothing and would gain an important constraint on nuclear weapons proliferation that could pose a threat to its security. It is past time to reconsider and ratify the treaty.