Not saying you're wrong, just making conversation. I wouldn't consider either a Cold War movie.
Not only does Quiet Earth have one of the coolest final shots in movies, it has a marvelous end title music cue. I'd say it's more metaphysical than Cold Warian. If that's a word.
Ok I see where you are coming from. :-)
"Panic" was an aftermath nuke war movie
and "Quiet Earth" was indeed very strange. :-)
However, "Countdown to Looking Glass" was fabulous. Check it out on IMDB and who was in it. (Hint, on of the actors was "the" Newt Gingrich himself :-))
(I have that one on DVD)
Another I really liked, however it was not really cold war was the movie "The Disappearance Of Flight 412".