All of the following events occurred during the 1960s except __________.

The Watergate scandal led President Nixon to resign in 1974, which was in the 1970s, not the 1960s. The Soviet invasion of Czechoslovakia, Cuba’s declaration that it was a Communist nation, and the U.S. U-2 plane being shot down all occurred during the 1960s. Therefore, the event that did not occur in that decade is the Watergate scandal forcing Nixon to resign.

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