We are not talking about 20 years, it is only 5 years from now. There is no sign that China emission rate slowing down. Chinese leaders do not make cutting GHG emission as their priority, and that is not helping. History means very little here, and we cannot wait till we got the point of no return. Even during Bush era, the US CO2 emission had been decreasing. We also elected an administration that makes alternative energy a high priority even during economic crisis. What has China been doing since 2000? Kyoto Protocol doesn't put cap on countries like China, and it is definitely not enough.