I take a hard view on this one:
In my opinion North Korea has seen a splinter in the two real entities, UN and NATO, that are holding it in check. I unlike others don't blame the US on this one I actually blame France for not looking ahead. Though I don't agree with how we handled the war situation, France has been more schizophrenic lately than anyone in Dorthea Dix (look it up if don't know what DD is). What I mean is if they didn't want war they should have struck down 1441 but they voted for it knowing that the US was going to go to war and they would protest it. NK sees the contradiction and goes out on a limb to make gains on our separation from allies.