How close did Germany come to perfecting an atomic bomb in 1945? Different therories about. The Soviet Union was keeping an eye on how far Americans were to nuclear weapons. Indeed, Nagasaki was chosen as the USA didn't want Stalin to think they only had one bomb. Historians argue over whether the Nazis were as close as six weeks to making a viable bomb to the other extreme of "several years" after Norwegian facilities were sabotaged by the resistance.