I'm not saying we shouldn't be paying attention and be mindful of the issue but this sort of problem has been around for most of my 60 years. It hasn't gotten much better in my lifetime but it hasn't gotten much worse (overall) either.
Well not soon. I'm not saying a war with North Korea won't happen but it won't happen for at least a few years. Right now our nation is to concerned with Afghanistan and Al Quada to pay North Korea any attention. And North Korea damn sure isn't going to declare war on America since they already have three enemy countries in Asia to worry about. Between South Korea, China, and Japan, I don't think we have anything to worry about. And no China isn't allied with North Korea. China hates that little prick almost as much as South Korea does.