Why did the US suffer a loss of confidence following the launch of Sputnik I?

The United States expected to lead in space exploration, so the Soviet Union’s successful launch of Sputnik I in 1957 came as a surprise and damaged confidence. It showed that the Soviets had reached space first, not that the US could never build a satellite. The best choice is “The US assumed that they would be first into space, before the Soviets.”

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