Even if the China-U.S. agreement were to be implemented, it still would not mean that the world would avoid an eventual two-degree increase in average temperatures, but that is no excuse not to do what we can. The other key point is that although China and the U.S. are responsible for approximately 44 percent of global greenhouse gas emissions, their agreement will clearly be worthless if they cannot bring the other major industrialized and industrializing countries on board. Both nations will have to display a considerable degree of leadership, which this bilateral agreement might well facilitate.

The greatest obstacle to the implementation of this agreement will lie not in China but in the U.S. This is not because President Obama was not sincere in concluding it; it is because he may not have the capacity to deliver. When President Clinton signed the Kyoto agreement in 1997, he was not able to procure ratification from a hostile Congress. Obama now faces the same problem. Even if his opponents believed there was a good case for such climate change agreements, they would refuse to support them simply out of opposition to the president. Moreover, U.S. Republicans rely on the support of many Americans who refuse to believe in climate change at all, so they will always misrepresent the situation wherever possible, as is clear from the statement of Senate Republican leader Mitch McConnell: "The agreement requires the Chinese to do nothing at all for 16 years, while these carbon emissions regulations are creating havoc in my state and other states around the country." In fact, China will have to do a great deal to ensure that growth in carbon emissions peaks by 2030. The point is that the level of debate on this issue in the U.S. is not conducive to effectively implementing the agreement, especially since the country allows private economic interests to have a disproportionate influence over its ostensibly democratic politics. And, of course, if opposition to the climate change agreement can be represented as anti-Chinese, this will also boost the Republican electoral effort in the run-up to the 2016 elections. (This consideration will, of course, also apply to the global conference planned for Paris in December 2015, so it is difficult to see how President Obama will be able to deliver on anything he promises there.)

What is needed here is pragmatism. Attaining a global climate change agreement will require some extremely sophisticated asymmetrical diplomacy - asymmetrical because it is impossible to claim that the two sides start from entirely equal positions in regard to climate change. It would be a fatal mistake for the U.S. and China to fall away from the goodwill expressed during Obama's visit to Beijing and start regarding each other as rivals who must be visibly defeated. The more both governments can do to help each other overcome domestic and shared concerns, the better our prospects of securing a cleaner world for future generations.

The author is a columnist with China.org.cn. For more information please visit:http://www.ccgp-fushun.com/opinion/timcollard.htm

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