However, they have to do something after so much rhetoric, or his grip on power would be threatened. There could be lot of domestic political infighting in Pyongyang. Lately, their rhetoric is way over the top even for NK standard.
Backing down from it as if nothing happened would damage his political credibility, sowing serious doubts on his leadership.
I think this time around China did lean on NK. NK cannot count on automatic aid which allow them to survive. They can deal with no aid from the West and SK. It is not the first time. China used to fill the gap. This time it does not seem to be the case.
Bump