Keeping track of the stuff bombs are made of

Sixty years ago, the United States triggered the nuclear arms race with the former Soviet Union by dropping the atom bomb on Hiroshima. Now America and its former foe are engaged in a sometimes-clandestine and always-expensive effort to prevent terrorists from getting the stuff that bomb was made of. “We are in a race between cooperation and catastrophe and the threat is outrunning our response,” former Georgia Sen. Sam Nunn said in a recent speech. The Hiroshima bomb, which killed more than 100,000 people on Aug. 6, 1945, used highly enriched uranium as its explosive, unlike the plutonium bomb tested three weeks earlier at the Trinity site in New Mexico or the bomb dropped on Nagasaki three days later, on Aug. 9, 1945. The Hiroshima bomb was a simple “gun” device that fired one block of uranium at another block of uranium. Weapons-control experts say this is the type of atomic bomb that is within the means of a terrorist group like al Qaeda to make, if its operatives could steal or buy about 55 pounds of highly enriched uranium. Fortunately, that’s still a big if. Full Story