The USA has to learn to let dictators live in peace. If they hadn’t invaded Iraq, and toppled Libya, young Kim wouldn’t feel the need to escalate in the first place.
So many of our contemporary problems come from the fact the US has seriously mismanaged it’s role of “Global Policeman”, and in particular the short-sighted Western desire to “spread democracy” (although this is normally just a sham argument to get the electorate to go along with invading other countries).
When Blighty had an empire, we mismanaged that, but the big gamechanger is nuclear weapons. People have largely forgotten about them since the ending of the Cold War, but in the last 20 years the US in particular has been busy developing a new generation of hydrogen bombs. These things are so powerful they can destroy whole countries, never mind cities.
I can’t really see a way out of Armageddon, I think it is inevitable, it’s just a question of when. But I don’t think it will come down to N Korea; I think the Middle East is where the action will be (as predicted by the good book).