may 1, 1960 - U-2 Incident
Description:
An American U-2 spy plane was shot down over Russia and the pilot was captured. Initially the US claimed that it was a weather plane that had gone off course but once the Soviets provided evidence to the contrary Eisenhower confessed that they had been spying in the USSR. This convinced Soviet leader Nikita Khrushchev that the US could not be trusted and it was pointless to negotiate. However, previous planes had shown that the USSR had much less advanced as well as much fewer nuclear weapons than Khrushchev had claimed.
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