US atomic test The nuclear age dawned with the explosion of bombs over the Japanese cities of Hiroshima and Nagasaki in August 1945, the culmination of the top secret Manhattan Project.
America retained a monopoly of A-bomb production until the first successful Soviet test - 'Joe 1' - in August 1949 in part owing to vital information supplied by the traitor, Klaus Fuchs, a physicist who had worked on the bomb at Los Alamos.
This was the point when the arms race - hitherto one involving conventional weapons - commenced in earnest.
The next stage was initiated in 1952 with the US test of the world's first hydrogen bomb, a fusion device of far greater potential yield than the atom bomb. The USSR responded the following year with a similar version of the H-Bomb.
In this exhibition
- World War Two
- Cold War begins
- Balance of Power
- New millennium