Problem for lil Kim is that he called off the armistice. Technically we were always at war with NK just in a cease fire. We already HAVE the authority to go in, should we deem it worth the effort. We won't until baby Kim actually makes a real move, but should he tick us off enough, we're already in a(legally) declared war with North Korea and have authorization to beat them to a bloody pulp... The only question is if China would step in and defend them. I think so long as it stays conventional, China would turn their backs...
"I would rather be exposed to the inconveniences attending too much liberty than to those attending too small a degree of it." Thomas Jefferson