On June 19, 1953, Julius and Ethel Rosenberg became the first civilians to be executed for espionage in U.S. history. The couple had been found guilty of conspiring to transmit atomic secrets to the Soviet Union.The Rosenberg case began with the arrest of Klaus Fuchs, a German-born and U.S.-employed scientist who confessed to passing classified information about the U.S. atomic program to the Soviets. Following his 1950 conviction, U.S. authorities began an extensive investigation of Los Alamos, New Mexico, the top secret U.S. atomic development headquarters, where Fuchs worked during the war. Harry Gold, a Swiss-born chemist, was arrested as a Fuchs accomplice, followed by David Greenglass, who had worked as a machinist at the Los Alamos atomic testing site during the war. In July 1950, Ethel Rosenberg, the sister of Greenglass, was arrested along with her husband, Julius, an electrical engineer who had worked for the U.S. Army Signal Corps during the war. Both were active members...