Hans Bethe believed that without John von Neumann, the development of modern computers would at best have been delayed ten years or more.

FORBES: A Veterans Day Story: Immigrants and the Atomic Bomb

The most significant work was done by Eugene Wigner (who came from Hungary), George Gamow (Russia), Felix Bloch (Switzerland), Hans Bethe (Germany), Edward Teller (Hungary), and Victor Weisskopf (Austria).

FORBES: A Veterans Day Story: Immigrants and the Atomic Bomb

The letter was drafted by Hans Bethe, who headed the group that designed the world's first nuclear bombs and who has served as a senior adviser to previous presidents on nuclear and anti-ballistic missile issues.

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