The international treaties and arrangements meant to keep nuclear weapons from spreading to terrorists may not be working, U.S. Defense Secretary Donald Rumsfeld said. The U.S. official also called on “responsible” nations to craft a new set of political, economic and “if necessary, military steps” to prevent the weapons from falling into the wrong hands. “I rank the problems we’re facing with the proliferation of these technologies, enormously lethal technologies, vastly more lethal than anything the world has known, to be a problem of the first order,” Rumsfeld said en route to Europe to meet with other NATO ministers of defense. North Korea announced Wednesday it would be restarting a nuclear reactor, which U.S. officials fear could be used to reprocess plutonium, a central ingredient for a powerful nuclear weapon, The Washington Post reported. Full Story