WASHINGTON—More than a decade after the Cold War ended, the world faces a possible "perfect storm" of security factors that has increased the risk of an accidental or unauthorized nuclear exchange between the United States and Russia, experts said yesterday.

A study by the RAND think-tank, strongly endorsed by former U.S. senator Sam Nunn and his non-profit group The Nuclear Threat Initiative, paints a devastating picture of Russia's strategic capabilities and challenges assumptions about the degree to which better U.S.-Russian relations have improved security.

In the report and at a news conference, they called for world leaders to address the problem.

The chilling assessment came as the Republican-dominated U.S. Senate cleared the way for research and development of a new generation of low-yield nuclear weapons, up to about a third as large as the bomb dropped on Hiroshima in World War II.

A day after senators voted to lift a 10-year-old ban on such weapons research, Democrats sought a compromise that would allow the research, but prohibit the development. Senators instead approved lifting the ban on both research and development, but would require the American president to seek congressional authorization before producing any of the new weapons.

"This issue is as clear as any issue ever gets: You're either for nuclear war or you're not," said Democratic Senator Ted Kennedy. "Either you want to make it easier to start using nuclear weapons or you don't."

New Scientist magazine, meanwhile, reports that the British government is recruiting scientists for its nuclear weapons program, raising fears among anti-nuclear campaigners that London may join Washington in developing new-generation nuclear weapons.

Britain's Atomic Weapons Establishment has confirmed it hopes to hire 80 physicists, material scientists and systems engineers this year and to increase its work force by 300 or more by 2008, the magazine says.

The scientists may be involved in research with the United States under a mutual defense agreement.

Nunn said the post-Cold War era has seen lessened chances of a premeditated nuclear strike by Washington or Moscow, but "on balance my belief is that the risk has increased ... for a perfect storm in terms of a nuclear miscalculation or an accident."

The RAND study cites three reasons for this:

• First, the United States and Russia retain large nuclear forces on "hair-trigger" alert, meaning they could be launched in minutes and destroy both societies in an hour.
  
• Second, economic and social problems have led Russia to rely increasingly on nuclear arms.
  
  The number of Russian weapons that could survive a U.S. first strike attack has declined dramatically, its submarine fleet has been "decimated," its early warning system has deteriorated to the point of "serious disrepair," and many of its intercontinental ballistic missiles are "well beyond their planned service lives," the report says.
  
  Moreover, "the breakdown of order in Russia, economic difficulties, and low morale of its military personnel and the rise of organized crime and separatist violence have increased concern" about nuclear force security, it said.
  
• Third, the vulnerability of Russian forces is enhanced by the increasing capability of U.S. forces to deliver accurate and devastating strikes, the report concluded.

All this means "the incentive (for Moscow) is to launch quickly — use it or lose it," said David Mosher, one author of the study.

The report foresaw three scenarios: an intentional unauthorized nuclear weapon launch by a terrorist or rogue commander; a missile launched by mistake; or an intentional launch of nuclear weapons based on incorrect or incomplete information.

With files from Associated Press

Copyright 2003 Reuters Ltd

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