Making an Improvised Nuclear Device
The second nuclear threat is that a non-state actor could acquire sufficient fissile material such as highly enriched uranium (HEU) or plutonium to build an improvised nuclear device (IND). An IND could have as much explosive yield as the bombs that destroyed the cores of the cities of Hiroshima and Nagasaki. Nuclear security experts agree that HEU poses the greatest danger because of the relative ease of using it to make a “gun-type” IND, similar to the bomb dropped on Hiroshima. In contrast, plutonium could only be used in the more technically challenging “implosion-type” bomb that was dropped on Nagasaki.
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