While Marine Recon got its start in World War II, with the Raiders and the 1st Marine Division’s Amphibious Reconnaissance Company, much of what Recon is today is thanks to Marine Test Unit 1.
After the nuclear bombing of Hiroshima and Nagasaki, most of the US military started trying to shift their doctrine to a model of a nuclear battlefield. At the time, it was assumed that nuclear weapons would become an integral part of warfare, much like gas had in WWI. As a result of this shift in doctrine, the services started looking at how to operate in a nuclear environment.
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