There was a nuclear war planned for 1953. That was the last year of complete american nuclear superiority over the commies. But of course the soviets had already gotten the plans thru leaks and spies. McCarthy was essentially right but just doing a rearguard action. From 1954 on the soviets could have successfully attacked the US and killed the whole civilian and military command. The focus turned to retaliation on Russia by the strategic air command and silo based misseles. It really was one nation under God.
Thats all the change in the anthem means. No religious meaning at all, no salvation. An inside joke. A tale told by an idiot or madman. The cold war ended and neo colonial proxy wars began.