Nature 449, 517 (4 October 2007) | doi:10.1038/449517b; Published online 3 October 2007

Nukes: next generation not fit for certification

Geoff Brumfiel


US design for nuclear weapons meets fresh disapproval.

The Bush administration's controversial plan to replace its cold war stockpile of nuclear weapons with a new, 'safer' nuclear arsenal has met with fresh criticism. An independent panel of scientists has concluded that ?substantial work remains? before the next generation of warheads is fit for certification.

In a report released on 1 October, the JASON defence advisory group, which consults regularly for the government on a range of technical issues, said there was insufficient peer review over the design for the Reliable Replacement Warhead (RRW). The RRW is to be built without compromising a 1992 US moratorium on all nuclear tests. The report also calls for an extensive battery of non-nuclear 'subcritical' tests to ensure that the new warhead will work as required.

Panel-member Roy Schwitters, a physicist at the University of Texas in Austin, says that the design's ?approach is valid?, but ?in lieu of new underground tests, we feel that peer review should have a bigger role? in the certification process. At present, the internal peer-review process of the three involved labs looks only at aspects of the design, not the entire system, he says.

Peer review should have a bigger role in the certification process.

The agency responsible for maintaining the US nuclear stockpile ? the National Nuclear Security Administration (NNSA) ? claims that the RRW would be more dependable than the current generation of cold war weapons. It would also contain new safeguards that would prevent its use if it fell into the hands of terrorists. But arms-control advocates say the programme is a costly handout to the nation's nuclear weapons laboratories and, they say, questions about the RRW's design could lead to renewed testing.


The report is a further setback for the programme, which is already under enormous congressional scrutiny, says Jeffrey Lewis, an arms-control expert at the New America Foundation in Washington DC. ?It suggests that the NNSA did a poor job in putting together a certification plan,? he says.

This week, the NNSA also reported that its dismantlement of deployed warheads had accelerated by 146% over the 2007 fiscal year ? three times greater than it had anticipated. Under the 2002 Strategic Offensive Reductions Treaty with Russia, the United States is committed to reducing its warheads to between 1,700 and 2,200 by 2012.