I'm not characterizing whether China has an obligation to do something about it and we don't. I'm just observing that China must have been cool to any overtures regarding global conservation (if it even came up, and I can't believe it didn't).
I have a hard time believing that "global conservation" of any kind would have come up in those meetings. In fact, for the U.S. to even suggest that global conservation of anything is a good idea is so silly it's childish.