The Economist just published a chart showing (on the left) annual CO2 equivalent emissions for different nations -- as part of its coverage of upcoming Copenhagen negotiations.
The U.S. looks pretty awful here, leading the world with 24 tonnes (we're #1! we're #1!) - and unfortunately these numbers are misleading. Sadly, I'm not helping the U.S.' case out on this one. These figures (based on U.N. calculations) significantly understate the U.S., and other wealthy nations' emissions on two counts.
First, they're based on the emissions in a given country's borders -- i.e. from the factories, power plants, cars, etc. working inside that country. Which means, if I buy a laptop manufactured in China, all the CO2 emissions from manufacturing that laptop (and it's a lot) are blamed on China -- when the true cause of those emissions is me, a U.S. citizen. This distortion breaks down into two parts. First, we import more than we export - we're running a trade imbalance. Then, to make matters a lot worse, the U.S. imports dirty, manufactured stuff, and exports clean stuff (Hollywood movies, financial services, consulting, software, etc.). Which means that even our net trade imbalance (roughly 6% of GDP) understates our net trade carbon imbalance (10% of GDP? more?).
Another hidden factor here is airplane emissions, which are counted by the amount of actual CO2 emitted. CO2 emissions from airplanes, because of the altitude, actually result in an estimated 2x to 4x the amount of global warming as emissions at ground level (e.g. from your car). The figures here don't account for this multiplier. So rich nations, which count for a disproportionate amount of flying, end up looking a lot worse.
A rough estimate for the U.S. based on these two adjustments alone bumps the U.S. 24 tonne figure up to the high 20's, possibly 30 or higher. Which is pretty sobering when you consider that, to be truly carbon neutral, people can't emit more than roughly two (that's right, TWO) tonnes annually.
That means the U.S., to stop overspending its carbon allowance, has to cut its emissions by about 95%. Oh, and by the way, at a reasonable growth rate, the U.S. economy is expected to grow 2,000% over the next century, and over 30,000% in the next 200 years. And so on (the power of compounding).
So how, exactly, are we going to get global emissions down to 5% of current U.S. levels -- and keep them there?
Going CO2e neutral isn't some abstract concept. It's the only way to stop warming the planet, the only way to avoid disaster (and it's pretty weak for us to be effectively blaming developing nations for emissions from producing stuff that we consume).