I sure wish some of these armchair experts would take a few modern international economics/international business/comparative politics courses at the university level. China will put the boot down on NK before the U.S. is ever dragged into military action in the defense of SK. China does not want war with the U.S. In fact, the Chinese long-term strategy for global domination is just that -- long-term. They have a 500 year plan in place and it's moving along just like it's supposed to. There's no need or desire for any more World Wars. The cost would be too high to the planet. The future is about peaceful indebtedness and the slow rise of Asia into an extended seat of power.