While this is all true, we continue to ignore mitigation measures and instead, focus on escalating our rhetoric. Which, in turn, feeds North Korea's paranoia.
Instead of focusing on North Korea's nukes and missiles, which the article rightly points out is a non-starter for the regime, we *CAN* focus on negotiations to reduce North Korea's ability to use them. For North Korea has a narrow set of reasons that would trigger their use.
That being:
1. Regime survival
2. Keep Japan/US out of any new Korean war.
So if we negotiate for North Korea troop reductions in return for a peace treaty. we eliminate both of their nuclear weapon trigger points. For the North Korea leadership believes that a peace treaty will ensure their survival (not kidding, it's one of their chief demands)... and reduced troop strengths will make it even more impossible for them to start a war on the peninsula (which is the only time they might use them).
This is possible as the North Korean's military pride is now focused on their nukes and missiles, not their conventional forces. In essence, North Korean leadership is 'distacted' by their new, shiny toy.
Then, after some time, we might come back and negotiate a nuclear weapons-free peninsula under the guise of "what's the point now?"