World and Nation

U.S. faces choice on new weapons for fast strikes

WASHINGTON — In coming years, President Barack Obama will decide whether to deploy a new class of weapons capable of reaching any place on Earth from the United States in less than an hour and with such accuracy and force that they would greatly diminish America’s reliance on its nuclear arsenal.

Yet even now, concerns about the technology are so strong that the Obama administration has acceded to a demand by Russia that the United States would decommission one nuclear missile for every one of these conventional weapons fielded by the Pentagon. That provision, the White House said, is buried deep inside the New START treaty that Obama and President Dmitri A. Medvedev signed two weeks ago in Prague.

Called Prompt Global Strike, the new weapon is designed to carry out tasks like picking off Osama bin Laden in a cave, if the right one could be found; taking out a North Korean missile while it is being rolled to the launching pad; or destroying an Iranian nuclear site — all without crossing the nuclear threshold. In theory, the weapon will hurl a conventional warhead of enormous weight at high speed and with pinpoint accuracy, generating the localized destructive power of a nuclear warhead.

The idea is not new: President George W. Bush and his staff promoted the technology, imagining that this new generation of conventional weapons would replace nuclear warheads on submarines.

In face-to-face meetings with Bush, Russian leaders complained that the technology could increase the risk of a nuclear war because Russia would not know if the missiles carried nuclear warheads or conventional ones. Bush and his aides concluded that the Russians were right.

Partly as a result, the idea “really hadn’t gone anywhere in the Bush administration,” Defense Secretary Robert M. Gates, who has served both presidents, said recently on ABC’s “This Week.” But he added that it was “embraced by the new administration.”

Obama alluded to the concept in a recent interview with The New York Times, saying it was part of an effort “to move towards less emphasis on nuclear weapons” while ensuring “that our conventional weapons capability is an effective deterrent in all but the most extreme circumstances.”

The Obama national security team scrapped the idea of putting the new conventional weapon on submarines. Instead, the White House has asked Congress for about $250 million next year to explore a new alternative, one that uses some of the most advanced technology in the military today as well as some not yet even invented.

Under the Obama plan, the Prompt Global Strike warhead would be mounted on a long-range missile to start its journey toward a target. It would travel through the atmosphere at several times the speed of sound, generating so much heat that it would have to be shielded with special materials to avoid melting. (In that regard, it is akin to the problem that confronted designers of the space shuttle decades ago.)