Originally Posted by machievelli
Actually, I think it would be the other way. If Kim attacked South or we attacked North, and Kim did not hit the nuke button, China might actually assist as long as he refrained. But you're right that after sixty years of supporting Korea, and watching them go to hell in a hand basket because of their mix of Communist rhetoric and a rule closer to a monarchy, China may just sit there and watch him get steamrollered and hope someone sensible replaces Kim.
Remember this as well, if that happens; of all the nuclear nations. as in ones that wwere known to have the bomb, what nation A: tried to get them banned worldwide? and what other nation actually stepped back from that cliff, dismantled their production facilities, and convinced the new government to foreswear ever redeploying them?
It's only my opinion that China won't join. I find it highly probable that China would value the trade relations with the US(look for stuff that DOESN'T say "Made in China"), as well as being fed up with defending NK and claiming they were not making nukes... Then proven wrong. It's an embarrassment to China that a government they supported went as far as they did.
And technically it was the US that started attempts at preventing nuclear proliferation(Ohhhh the irony/hypocrisy of that).