An equal right to pollute?

Happy New Year! I'll kick off 2010 with an interesting idea from Bono, via Owen Barder:

An Equal Right to Pollute (and the Polluter-Pays Principle)
One smart suggestion I’ve heard, sort of a riff on cap-and-trade, is that each person has an equal right to pollute and that there might somehow be a way to monetize this. By this accounting, your average Ethiopian can sell her underpolluting ways (people in Ethiopia emit about 0.1 ton of carbon a year) to the average American (about 20 tons a year) and use the proceeds to deal with the effects of climate change (like drought), educate her kids and send them to university. (Trust in capitalism — we’ll find a way.) As a mild green, I like the idea, though it’s controversial in militant, khaki-green quarters. And yes, real economists would prefer to tax carbon at the source, but so far the political will is not there. If it were me, I’d close the deal before the rising nations want it backdated.

This sounds attractive, but it shares problems with the "carbon intensity" pledges that China has offered. For overall emissions to be reduced (or even levelled), the "average" right to pollute would be quite low (I'm guesstimating 1-4 tons a year based on relative rich/poor populations in the world), so it requires Americans and other rich-world citizens to pay for virtually all of their pollution... except unlike cap-and-trade, where the money goes to their governments (and much of it ends up rebated), all of that money goes to poor countries. Once that math is laid out... how exactly is this more sellable than what failed to be agreed upon in Copenhagen?