The NYT lede: Obama wanted China to be more transparent on the cuts they’re to make, but also wanted an agreement - no matter how imperfect - to be done before work wraps up.

Sometimes the only thing worse than no deal is a bad deal, and I think that most countries think that this is a bad deal. Of course, Obama can agree to whatever he wants, but if Congress doesn’t approve, the US wont be bound by the Copenhagen protocol just as surely as President Clinton didn’t even bother submitting Kyoto to Congress because they would never have accepted it.

Obama can make all the demands he wants, but if something is accepted, he can turn around and blame Congress for not getting it adopted; he’s still the President and has to play politics with Congress over this.

A profile of the competing interests is here (the various national/transnational groups).