Okay, if we're talking less than 5000 Km then we're talking launching from Canada, Mexico, or a sea vessel.

I think we can safely rule out Canada and Mexico, so that leaves sea vessels. I personally have enough faith in our Navy intel capabilities that I don't worry in the least about that scenario. I think our seas are watched pretty closely, vessel-wise, together with the Navy, and the Coast Guard's drug smuggling surveilance.

I think ICBMs are the only real threat we have missle-wise outside of conventional war, and I think that possibility is extremely remote given the other threats that face the nation today. As crazy as Kim is, I don't believe he's crazy enough to preemptively push the button.