The Myth of the Sarbamba

The Sarbamba was nominally 50 megaton monster that was just made to show off. A fusion weapon works very roughly like this: You have an atomic bomb, one with uranium or plutonium, that explode. And these create enough energy to squeeze the atoms of a secondary stage made of hydrogen together,. creating a fusion. If they had really used the initial 100 megatons design, it would have double the fallout in 1961 globally.