From the Financial Times, in a piece about the pending California greenhouse gas emission bill:
The United States is the world’s largest producer of the heat-trapping gases that many scientists link to extreme weather like violent hurricanes and rising sea levels.
But Bush pulled the United States out of the 160-nation Kyoto Protocol to cut greenhouse gas emissions in 2001, arguing that it would hurt the economy and unfairly excluded developing nations like China. I, like the author, think global warming sucks. But from the facts he presents in the article, it’s not clear that American emissions caps would have much impact on the phenomenon. Suppose that each year, every country in the world was producing one unit of pollution, except that the US was producing two. The US would then be the world’s largest producer of pollution. But reducing our emissions by 25% (which is what Gov. Schwarzenegger hopes to achieve by 2020) would have no effect.