on a more serious note:
we can't nuke north korea, nor can they nuke us. if we nuke north korea, we're asking china, russia to go to war with us, and south korea to dissalign themselves with the US. if north korea nukes the US, everyones on their ass, even china and russia. so the only thing left to do in a war would be massive artillery bombardment. it would be the blitz only successful. but then north korean nationalist guerrillas would be a problem, and we'd be in their country for 20 years try to reestablish a unified korea under a democratic leadership. and then north korea would do what germany did to the third reich and burn everything the north koreans were ever involved with.