Or do you think China trusts Kim anymore than we do? That Kim is any less likely to try extorting them if he thinks he can get away with it? I think China is playing an incredibly dangerous game with a very unstable personality; they don't want to let him get so far away they can't control him (and North Korea would collapse in a month without every kind of aid you can think of coming from China, so they CAN control him if they so desire) but they don't want to appear so close to him they're seen as complicit in his behavior. That's what this whole absurdity about six party talks is about, the conceit that China can't keep North Korea in line, but they'll listen to Russia, South Korea and Japan. The first and the last of those nations fought a war over control of Korea a century ago, and, of course, South Korea has been in armed conflict with North Korea for about half the time since, so I really don't think they can convince North Korea if the superpower propping them up can't.

Tom's right, IMHO, but I've long held that opinion: North Korea isn't there just to provide China a proxy, it's there to antagonize and possibly even nuke Chinas enemies, get obliterated by the retaliation and leave China to go her merry way untouched.