The height of the cold war, and both America and Russia were merrily detonating nuclear weapons in the atmosphere (soon to joined by England, France and China). This shows how an A-bomb blast affects a mock town. The footage is truly awesome, but also I was stunned at how close they allowed people to get to the blast, and how unprotected the researchers were who went into the town afterwards. I'll bet that many people were exposed to high doses of radiation. Happily, atmospheric testing ended a decade later, and even underground tests are rare these days. But there are still many thousands of nuclear weapons around, far more powerful than this 1955 blast. When will we finally get rid of them?