I really don't think war is either, a realistic option (unless NK strikes a key target) or in the actual strategic interests of the US in this region. An article (William Endgahl) I read a while back sums up the NK situation pretty well, IMO;
(Excerpt) In the event, in our Davos discussion we touched on events in Asia and the ongoing focus by Washington on North Korea’s nuclear program. Unexpectedly, Lilley made a remarkable statement to me. He said, “Simply put, at the end of the Cold War, if North Korea didn’t exist we would have to create it as an excuse to keep the Seventh Fleet in the region.1” Shortly before our Davos discussion North Korea had launched a missile over Japan, causing huge anxieties across Asia.