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Bush buries US bunker-buster project

Plans for ground-penetrating nuclear warhead scrapped.


Bowing to congressional pressure, the administration of President George W. Bush has killed a programme to design a nuclear warhead capable of striking targets buried deep in the ground. It has instead chosen to develop replacement warheads for the existing nuclear stockpile.

The cancelled weapon, called the Robust Nuclear Earth Penetrator (RNEP), was proposed three years ago (see Nature 415, 945; 200210.1038/415945a). It was to have been a toughened version of an existing warhead that could strike bunkers and other underground targets.

However, some physicists were sceptical that the warhead, known as the ‘bunker-buster’, could penetrate deeply enough to contain its massive nuclear blast. A National Research Council study released in May showed that the weapon would be highly effective at destroying deeply buried targets. But casualties could still number in the thousands, says John Ahearne of the scientific research society Sigma Xi, who chaired the study.

Within Congress, Republicans and Democrats alike opposed RNEP development on both political and technical grounds. Last year, a bipartisan coalition killed funding for the programme. In the face of such opposition, the administration has essentially pulled the plug on the project by withdrawing the $4 million requested to study RNEP, according to Senator Pete Domenici (Republican, New Mexico).

“The focus will now be with the defense department and its research into earth-penetrating technology using conventional weaponry,” Domenici said in a statement.

“This decision simply confirms what the critics have been saying all along,” says Christopher Paine, a senior analyst at the Natural Resources Defense Council. “The programme had become a thorn in the side of the administration.”

But as RNEP disappears, another project is on the rise. A congressional budget bill expected out this week would allocate $25 million to speed up the Reliable Replacement Warhead project. The programme, established to design the next generation of weapons for the ageing nuclear stockpile, has itself been generating controversy among researchers, some of whom believe it to be unnecessary (see Nature 434, 684; 200510.1038/434684b).

“RNEP may be politically dead,” says Daryl Kimball, executive director of the Arms Control Association in Washington DC. “But I would be very surprised if the debate over new weapons ends any time soon.”


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National Research Council report - Effects of Nuclear Earth-Penetrating Weapons

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Brumfiel, G. Bush buries US bunker-buster project. Nature 438, 139 (2005).

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