Both of those things are already things that we have and do not need any more of to justify a full-scale nuclear war. I'm pretty sure the thing keeping it from becoming a real war zone is mutually assured destruction. Even mutually assured destruction aside, I think most people realize whatever kind of conflict occurs it won't be pretty for the parties involved.

Of course, letting things go for long enough to actually allow North Korea to produce working nuclear weapons is probably not very smart either, but I guess hindsight is 20:20.