North Korea has recently once again done a bit of missile tests, which US and most of the world condemn as war-mongering. But US has an aircraft carrier on the way and China has been vocal about sending troops near border, so this state of terror is just a show for both sides, as usual.
Anyone can probably speculate on who would win a war if and if. In case NK, they would be sore losers and a war declared on either US, South Korea or China or Japan for that matter, would almost certainly result in destruction of North Korean system of power and ending the Kim dynasty of terror. They don’t either want to take a risk.
But NK is special. Most would agree a state in complete control of a crazy dictator is a threat to peace in nearby countries. NK possesses, if not well-equipped, at least a numerous army of men. Dilemma is, that longer they continue, better equipped they are.
Why really makes NK special, is that with their resources and total control of one man, who is not playing by any Geneva Convention rules. I would not suspect that they would not use CBRN-weapons and if a war would happen they would take many SK civilians with nasty tricks like biological weapons, gas last used in WW1 and dirty bombs, to name a few.