[@Arkaquiavel] Actually, if North Korea tried anything of major importance China would probably blitz them and just set up another opressive puppet government in the region. China wants a buffer state, not the whole peninsula. During the big showdown where it looked like the cease-fire might be broken last year, China stationed mobile forces on their border with North Korea in what appeared to be preparation for an attack. For all we know, that might have been enough to make them stand down. It really boils down to whether or not China wants to deal with beating back American attacks, occupying a heavily populated and vehemently independent South Korea, and risking the possibility of the total destruction of Earth's entire biosphere.