A Time of War.

The H-bomb, or hydrogen bomb, resulted from scientific research that developed from the atomic bomb, which was dropped on Nagasaki and Hiroshima in Japan to end World War II. The H-bomb technology follows from that required for the A-bomb, so H-bomb development did not begin in earnest until the 1950s.

Fission.

The A-bomb is based on nuclear fission. The nuclei of uranium atoms are bombarded with neutrons propelled from a magnetized coil. As a result, the uranium atoms are split (fission), releasing enormous amounts of energy. In addition, during the process neutrons are released, which can interact with even more uranium nuclei. The final product is a self-sustaining nuclear reaction that releases enormous amounts of energy. When this energy release is contained in a small area, it produces a bomb.

Fusion.

The H-bomb is based on nuclear fusion. Instead of splitting...