In a perfect world faced with climate change due to centuries of wrongdoings in the advanced industrial countries it would indeed be best if they started cooperating with the less developed countries belatedly bent on industrialization by helping them avoid the same wrongdoings through cap-and-trade policies such as those promoted by the Kyoto protocol (“A Convenient Truth, Sadly Ignored,” June 7, 2008). Financed by the rich countries, the poor ones would develop without contributing as much to climate change. But this is a spurious argument because climate change would hardly threaten a perfect world. In the world we actually live in, which is imperfect to boot, cap-and-trade policies you advocate are unlikely ever to work on a global scale. In their place, we are likely to have increasingly nasty trade wars under the banner of climate change. Instead of painting in glowing terms the world we do not live in, it would be much more useful to paint the consequences of incessant bungling in the world in which we actually do live. Maybe, just maybe, the horror lurking ahead would concentrate the minds around the world and thus help us avoid the worst pitfalls of imperfection.