Kim Jon Un has turned out to be nobody’s fool. North Korea’s launch of a missile which went high enough on test to be able to reach any target in the U.S. was not only impressive but ahead of the general view of their capability. This pattern of being ahead of the expectation is fairly consistent. We can assume that they are ahead of the general assumptions on both miniaturization and guidance. North Korea does not have the capacity to launch a nuclear strike on the United States tomorrow, but it is not as many days after as hoped, that they will be able to.
Kim Jon Un knows that if he decides one day take to hit Chicago and Los Angeles, or even New York, his country will be obliterated before that day is out. So what is his plan? It is very simple. He watched Iraq and Libya face not only regime change but state failure as a consequence of Western intervention. He calculated he was next on the list, or if not next, on it somewhere. Having a strategic nuclear capability to threaten the US is a sure way of bringing the US to recognise, with the rest of the West, that North Korea has to be shown respect as a nuclear power and negotiated with on equal terms.
Ultimately the official war between north and South Korea has to be ended. At the moment there is only an armistice. China wants a demilitarised Korean peninsular, which would involve the North giving up its nuclear weapons in exchange for recognition and peace. Absolutely nobody wants a war and certainly not a nuclear one. Looked at this way the gap between Trump and Kim Jon Un is not as wide as it seems. If China could host some kind of meeting between them, good would come of it.
It is certainly worth trying.