Manhattan Project The Einstein Letter Leo Szilard, like many other foreign-born physicists in the U.S. who had fled fascism, knew Germany was conducting nuclear research. Having learned the Germans had banned the export of uranium, he believed the Germans were developing an atomic bomb. Fearing what would happen if Germany developed a nuclear weapon, he urged Dr. Albert Einstein to convince the American government to support nuclear research. On August 2, 1939, a month before Germany …showed first 75 words of 847 total…

…showed last 75 words of 847 total…Klaus Fuchs, was a Soviet spy. He and other spies passed information about American nuclear research to the Soviets from 1942 to 1949. This could explain Stalin's indifferent reaction when Truman told him at the Potsdam Conference that the U.S. had a new weapon. Fuchs was caught and convicted of espionage, and sentenced to 15 years in prison for disclosing nuclear secrets. After his release, he went to East Germany to work in their nuclear research center.