The swift and sudden shift of the U.S. public's attention inward, though, might provide everyone with just the breathing space needed.
Kim Jong-un's government had painted itself and everyone else into a corner. It had ratcheted up tensions so alarmingly that it could not have avoided doing something to back up its belligerence. You don't issue such incendiary rhetoric as the North Korean government did and then just stand there: you look like a barking chihuahua, an irritating but basically harmless noisemaker. If you want people to take your barking seriously, you have to sink your teeth into somebody's leg.
The U.S. public's memory is short, though. Given a week or two of other, seemingly more pressing business at home — perhaps another disappointing development in the increasingly pointless gun "control" debate in Congress; maybe a controversial Supreme Court decision; or, heaven help us, another major explosion somewhere — the U.S., China and the two Koreas can quietly go about resetting their relations to the former status quo: uneasy, but calm.
Kim Jong-un couldn't possibly have imagined he would be able to step back from the brink. He's had a stroke of incredibly good fortune. If he has any of his father's or grandfather's brains, he'll take that step back and count his blessings. Then he and his advisers can figure out how to rattle the U.S.'s cage again down the line — but without getting so close to a fight that would destroy them.
That's what I hope he's thinking, anyway. If he, or whoever's advising him, is determined to press on, to create a crisis, we're all in a lot of trouble.
Prove you're at least as smart as your father, Kim Jong-un. It's your life that's hanging in the balance.