U.S. President Bush has often pointed fingers at China’s greenhouse gas emissions problems when explaining why he rejected the Kyoto treaty on climate change. Kyoto would require the U.S. to cap its carbon dioxide emissions, but places no such constraints on developing countries like China. However, China’s CO2 emissions have actually dropped in the last four years, even as its economy has rapidly expanded, according to data collected by the U.S. Department of Energy. Gao Feng, a senior Chinese Foreign Ministry official, said, “We’ve done what we can to reduce emissions, and we’ll continue to do so.”