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Weapons around the world
Aug 3, 2005
Nuclear weapons remain the most powerful force ever invented by humankind. They can be constructed with either highly enriched uranium (over 20% 235U) or plutonium. Most modern nuclear weapons rely on a combination of fission and fusion, using the initial nuclear release from a core of uranium or plutonium to ignite a secondary fusion of lighter elements. The first nuclear weapons developed by the US had explosive yields equivalent to 10-20 kt of TNT, while most of today's deployed weapons range from 100-500 kt in yield. In all, there are approximately 27,600 nuclear weapons in existence.
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