 The atomic bombings of Hiroshima and Nagasaki ushered in the "atomic age", and the bleak pictures of the bombed-out cities released shortly after the end of World War II became symbols of the power of the new weapons.On August 29, 1949, the Soviet Union tested its first atomic bomb, code named "Joe 1".Its design imitates the American plutonium bomb that was dropped on Nagasaki, Japan in 1945.