A U.S. National Academy of Sciences (NAS) committee report reviewing technical issues related to the Comprehensive Test Ban Treaty (CTBT) has concluded that the U.S. nuclear weapons Stockpile Stewardship Program “has been more successful than was anticipated in 1999,” when the Senate last considered and voted on the CTBT.
The report, which was released March 30, also said that “the status of U.S. national monitoring and the International Monitoring System [IMS] has improved to levels better than predicted in 1999.”
The study was requested by the Obama administration in 2009 following President Barack Obama’s call for “immediately” pursuing reconsideration and ratification of the treaty, which was signed by President Bill Clinton in September 1996 but has not yet been approved by the Senate. Although the report was completed in early 2011, its release was delayed by an extensive declassification review.
“[P]rovided that sufficient resources and a national commitment to stockpile stewardship are in place…the United States has the technical ability to maintain a safe, secure, and reliable stockpile of nuclear weapons into the foreseeable future without nuclear explosion testing,” says the report, which is by the National Research Council, the operating arm of the NAS.
Stockpile stewardship is the responsibility of the National Nuclear Security Administration (NNSA), a semiautonomous unit of the Department of Energy. Since 2009, funding for the NNSA nuclear weapons complex has increased by 13 percent. The Obama administration’s $7.6 billion budget request for fiscal year 2013 would boost the funding even more, by 5 percent over the fiscal year 2012 appropriation of $7.2 billion.
The NAS panel, which was chaired by Ellen Williams, a physicist and now chief scientist at BP, was charged with reviewing technical changes related to the U.S. nuclear stockpile and to nuclear explosion test monitoring that have occurred in the 10 years since the NAS’s 2002 report on the subject. The panel’s eight other members include former NNSA Administrator Linton Brooks; Richard Garwin, a veteran weapons designer and adviser to U.S. national laboratories; Adm. Richard Mies, the former head of U.S. Strategic Command; and former Lawrence Livermore National Laboratory Director Bruce Tarter. A subcommittee of seismological experts supported the panel’s investigation.
The panel’s 200-page report concludes that “[c]onstraints placed on nuclear-explosion testing by the monitoring capabilities of the IMS and…U.S. NTM [national technical means of intelligence] will reduce the likelihood of successful clandestine nuclear-explosion testing, and inhibit the development of new types of strategic nuclear weapons.”
The report finds 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) by appropriately resourced U.S. national technical means and a completed IMS network.”
The study concluded that an on-site inspection as permitted under the CTBT once it enters into force “would have a high likelihood of detecting evidence of a nuclear explosion with a yield greater than 0.1 kilotons, provided that the event could be located with sufficient precision…and conducted without hindrance.” The panel said on-site inspection “constitutes a deterrent to treaty violation whether or not an inspection actually takes place.”
The report found that “the development of weapons with lower capabilities…is possible with or without the CTBT for countries of different levels of nuclear sophistication, but such development would not require the United States to return to nuclear testing in order to respond because it already has—or could produce—weapons of equal or greater capability based on its own nuclear-explosion test history.” The United States has conducted 1,030 nuclear test explosions, the last of which was in September 1992 when Congress approved legislation mandating a halt to U.S. nuclear explosive testing.
Brooks said last November that “as a practical matter, it is almost certain that the United States will not test again. The political bar against testing is extremely high.”
“I have been in and out of government for a long time,” Brooks said, “and in recent years, I never met anybody who advocated that we seek authorization to return to testing.”