Because of the activities of people like Klaus Fuchs, Harry Gold, and David Greenglass, the 1940s and 1950s can be called an age of

Klaus Fuchs, Harry Gold, and David Greenglass were involved in passing information about the U.S. atomic program to the Soviet Union. Their activities were part of Cold War spying, so the 1940s and 1950s can be called an age of espionage. “Technology” is related to the atomic program, but espionage describes what these people did.

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