"My one concern is that Hu Jintao may overestimate how much power China has in Pyongyang. They have - they do have influence, and they do have companies, and they do have economic relationships that could make life much more difficult in the north. Their balancing act is, "How much worse can we make it in the north without creating that which scares us more than anything, which is a collapse in the north." And then what happens to all those nuclear weapons. So they're going to work very hard to avoid that."