@kpop. I disagree that North Korea can bring about a nuclear war - I'm assuming between the United States and Russia - since it's only ally, China, has neither the desire nor enough nukes to engage in a meaningful first strike.
It's complicated. South Korea had their election today and voted in an idiot who is a war mongering psycho. Moon said the current conservative gov is not doing enough to stop Kim and is already threatening with first strike. What do you think Kim will do? That will force the hand of China and Japan and drag the US into another terrible war. It could get ugly fast. Let's hope it never gets that far.