The US (Trump) should read Stephen Covey's "7 Habits."

If Trump was capable of reflection (never mind reading!), he should think about the concentric circles. There is the circle of interest, the circle of concern, and the circle of influence.

What NK is doing is certainly of interest to the US, and likewise is of some concern. But he has to accept that what is going on, as far as the development of nuclear potential, is for all intents and purposes outside his circle of influence.

That said, he can affect the actions of, and can provoke responses from Kim Jong-Un, and indeed is doing so. But he can't affect things in a positive and constructive way.

Simply put, he should stand down and shut up.

Let grown-ups and diplomats handle this one, and Trump can go back to haranguing football players for exercising their rights ;and freedoms under the 1st Amendment.