You are correct. Sadly, the past 4 administrations have coddled the NK’s and been mute about the reason NK exists at all.
Nothing is going to happen. The Chinese want to force the US to sign onto the gun treaty and they are using the Norks to play to our fears of destruction.
If we ignore the chump, in a couple of weeks he will declare that he blew up some obscure place in the US and North Korea won the war. Who in his country would know any better?
Clinton let them develop missiles and Obama fumbled on Nulear weapons develupment.
This is a very interesting analyses compete with maps:
http://www.futurescience.com/emp.html