How did Albert Einstein and J. Robert Oppenheimer support the war effort?

Oppenheimer led the Los Alamos laboratory, where scientists developed the first atomic bombs as part of the Manhattan Project. Einstein did not work on the bomb project, but he signed a 1939 letter warning President Roosevelt that Nazi Germany might develop atomic weapons, helping prompt U.S. government action. So the best choice is that they supported the war effort through work and advocacy connected to atomic weapons, not by fighting at the front or rescuing people from camps or ghettos.

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