91av

THE Comprehensive Test Ban Treaty is in crisis. In 1999, the US Senate decided not to ratify the treaty, claiming it is impossible to verify. Scientists involved with the International Monitoring System disagree.

But some observers believe there is a more insidious reason why the US is holding back, because it wants to resume testing nuclear weapons. “The Bush administration appears to be slowly but steadily removing the obstacles preventing a resumption of US testing,” says Daryl Kimball of the Arms Control Association, a think tank in Washington DC. The clearest sign of this has come from the administration’s Nuclear Posture Review, leaked in March. It stated that further testing may be required to maintain the US nuclear stockpile and to meet the threats posed by new enemies.

The review specifically calls for earth-penetrating nuclear weapons with a lower yield than conventional bombs. These would be designed to take out buried, hardened bunkers housing weapons or enemy commanders with minimal “collateral damage”. Such a weapon was proposed by military scientists nearly two years ago (91av, 7 October 2000. p 6), and a $50 million study of how to build such weapons has just begun at two US labs.

One way might be to convert the existing “burrowing” 5-kiloton nuclear bomb, the B-61 Mod 11, or modify the “primary” or first-stage explosive charge of an existing weapon. Either way, it’s highly likely the military will want to test such a device before taking it into battle.

And if the US restarts nuclear weapons tests, other countries might feel they have to follow suit. Last month officials in Washington accused Russia of preparing to resume nuclear tests on the island of Novaya Zemlya. The Russians could simply be taking precautions in the face of the American rhetoric over testing. But some Congressmen suspect the charges were aimed at stirring up the political will in Washington to resume tests.