Many principles of the Hydrogen Bomb are similar to the principles of the atomic bomb. The major difference is that after the nuclear reaction takes place, it is followed by a thermonuclear reaction, also called fusion. The main purpose of the nuclear portion of the bomb is to heat the gas (typically hydrogen or helium) to several million degrees, which is required for fusion to take place. The thermonuclear reaction releases additional energy, making the hydrogen bomb even more powerful that the atomic bomb. After 1945, Canada refused to aid the Americans and British in creating atomic or hydrogen bombs, claiming to help only in peaceful applications of nuclear energy. However, Canada continued supplying the US and the UK with uranium and plutonium, maintaining the status of a nuke-free country.

The photograph displays a thermonuclear explosion of a hydrogen bomb.