The trial of Julius and Ethel Rosenberg on charges of conspiring to spy for the Soviet Union remains one of the defining moments of the Cold War era. The dramatic allegations of stolen atomic secrets and networks of Communist spies riveted the public's attention. The determination of government prosecutors reflected a widely shared belief that the Rosenbergs and their ring of spies had enabled the Soviets to build an atomic bomb, bringing the world to the brink of a new kind of holocaust. The 1951 trial and subsequent appeals demonstrated the burden on the federal courts as they became a principal forum for challenging domestic espionage and suspected Communist subversion. The fate of the Rosenbergs divided public opinion in the United States and in Europe, and the memory of the trial would define political fault lines throughout the Cold War.