That's a really simplistic way of thinking about it.

The red scare continued through the late 1950s (and the cold war continued for decades -- there was no lack of fear and suspicion).

John Glen orbited the earth in 1962, in the middle of all this.

The nation doesn't wake up, flip and coin and decide it's either optimistic or fearful one day. You can be scared of some things and optimistic about others. Or both at the same time. Or some people are optimistic, and others have more fears.

It's complicated, but pithy quotes ("I'm just hoping for hope again") are stupid.