A massive military that will collapse when tested. A US backed South Korea would win any conflict but the price would be high.
Exactly this, some of the comments in here are idiotic. In any sort of conflict South Korea would suffer serious damage, regardless of nukes being involved or not.
Further, let's not forget NK also, (to some extent), managed to launch a satellite into orbit a couple of months ago.
Sure, they may lack resources, have outdated tech etc etc but they are perfectly capable of causing a mess locally.
Perfect "boy who cries wolf" scenario, NK are going to do something stupid one day and people will be slow to react after so many "empty" threats.
But yeah, any capability of targeting missiles at long-range targets (eg. U.S.A) (which they may have) is also widely inaccurate and/or unreliable.