I hope this doesn't sound too pathetic an analogy, but I'm reminded a little of fights between brothers. So often it starts off when the smaller brother gets loud or aggressive but, to start with, there isn't really a threat, he's such a puny weakling, and the older brother should just soak up the "hits" and maintain a sense of discipline. But that doesn't often last, and then it turns violent, and the little brother gets totally wrecked but big bro doesn't come out of the fight looking too good either.
It still holds that if North Korea actually starts anything serious then they'll be totally destroyed, because they have no allies if nothing else. Someone in NK must realise this, but perhaps it's also important for Trump to recognise that fact. He shouldn't need to threaten "fire and fury" in language that's just a little chilling, because he knows, we know, and North Korea surely still knows, that they will lose any fight. If indeed North Korea starts something then, of course, Trump will be well-justified in taking action against them; before that point, it seems in everyone's interest to try and de-escalate the threat of war and apocalypse (while being ready to respond if necessary). It's a little un-nerving that Trump looks to have an itchy trigger finger, is all...
But that presupposes that Kim Jong Un is rational, and maybe he isn't. If he carries on like this then maybe it really is time to turn round and clock him before it's too late.