NASA White Sands has a small visitor center that describes the basics of work conducted there since 1944. The Trinity Site is now open to visitors but they must sign a release that says they know they are going into an area that may still be radioactive after what must be the dirtiest weapon test America has ever conducted.
Results of Trinity allowed scientists at Los Alamos National Laboratory (now Sandia National Laboratory) to increase the burst of the "Fat Man" nuclear weapon and at the same time greatly reduce its radiological footprint.
God knows the use of nuclear weapons was the last resort, but without them we'd still be fighting WWII, probably in Russia and Manchuria.
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