While Western nations (certainly not just the US, but also almost all of Europe) have reached a democratic impasse in which very little changes, China seems able to reflect on changes internally and externally, and develop drastic new regulations when necessary. It can self-correct. I could give a long explanation why this is true, but Eric Li explained it a lot better in a TEDx presentation. It's 20 minutes, but very relevant when comparing governments of China and US (and other Western countries).
https://www.ted.com/talks/eric...
I would not be surprised if China adopts its own pollution and climate regulations that are beneficial for the country, where benefit can include anything they think is relevant: e.g. health, economy. And it might be that these are more strict than we have here, or not. Time will tell. But they will decide on their own terms. Don't forget that China has to import a lot of fossil fuels, while it has most (all?) resources needed to produce sustainable energy production (solar/wind), and they also already have the factories within their borders. There may be a large economic incentive too.
I see Obama's challenge only as an excuse for the USA's lack of action.