"What benefit can China get if North Korea possess nuclear power and perhaps grow strong enough to stand up to China...Surely China doesn't want that happen, does it?"
Probably not. But I don't see how anyone can deal with NK when the leader is insane.
hahaha..."the leader is insane"? well,that's how he is by your standards...He is just doing what he has to do to confront those countries who are hostile to it...