FDD, when I was in high school this is something we thought about alot, me and my friends. We lived in a city that was 80% retired or active duty military with four military installations, one of which put us number two on the USSR's target list, right after Washington DC, in a nuclear war. We knew that if we heard the air raid sirens it would be 11 minutes max before we were vaporised and that is if the DEW worked and caught them on launch as they came over the polar ice cap.
We would sit sometimes and think about what we would do... we couldn't run away fast enough to escape the fallout even if we got away from the fireball... the conclusion was that we wouldn't want to live through the fallout and die slowly over the next few weeks so we planned to grab a six pack, climb up on the roof and watch the show.
Black humour reigned as it usually does in these kinds of situations when people are faced with something so horrible and at the same time knowing you are completely powerless in the face of it to affect any change.
The world is much simpler when you're young.