I was a military brat, and grew up next to a large military base in the '80s. (Actually a few of them, but I'm thinking of one in particular.) As kids whose fathers manned the weapons of mega-destruction, we were well aware that Armaggedon was imminent through nuclear holocaust. Our proximity to the military base assured us that we would die instantly without becoming radioactive zombies -- our eyeballs would melt out of our eyesockets, we'd become ash, and our town would turn to glass.
Anyway, I read a lot of "men's novels" back then about American paramiltary specialists who survived the nuclear war and fought a bunch of ethnically-themed gangs and invading communists and fascists, usually by shooting at them with a machine gun while riding a motorcycle. "The Survivalist" series was my favorite, but "Out of the Ashes" had more explicit sex.
Paul Bryan has a nice synopsis of this bygone literary trend here.