Annon asks, "Do people generally understand that any serious global warming policy will raise energy prices quite a bit? Do you think a serious global warming policy is politically possible?" No, and define "possible." There's a reason politicians talk about something called "cap-and-trade" rather than a carbon tax, or a gas tax. "Cap-and-trade," which limits, and then reduces, the amount of carbon companies can emit, sounds more like the son of David Ricardo and a pirate ("yeargh, I'm Cap'n Trade!") than a massive tax. Better yet, unlike a carbon tax, which simply makes carbon more expensive, cap-and-trade functions through a somewhat complicated mechanism that you have to explain before you can say that it simply makes carbon more expensive. But fundamentally, that's the plan. And no politician wants to say so. The great bright spot for environmentalists is that John McCain won the Republican primary. Whether he knows it or not, he's got a cap-and-trade plan in his policy agenda. It's not an incredibly good cap-and-trade plan, but it's good enough that he won't be able to run against Obama by saying that Obama has a secret plan to make gasoline even more expensive, as John McCain also has a secret plan to make carbon more expensive. So both of them will try and downplay this fact, and instead talk about carbon auctions and pollution permits and the like. But then they're going to slam into Congress. Fundamentally, I'm pretty pessimistic about our ability to do anything proportionate on global warming. The basic problem is this: Our political system isn't very good at doing things in advance. Carbon emissions need to be stopped now in order to disrupt irreversible climate consequences later. Politicians work off short-term incentives, global warming is a question of long-term incentives. The bright spot is that the Lieberman-Warner climate bill -- which was insufficient, but more than nothing -- broke 50 when it came up for a vote this year. If the Senate decides to act as a body of legislators ad have themselves a world-saving, profiles-in-courage moment, they could in fact pass a serious cap-and-trade bill with backing from a President Obama. But that's a lot to hope for. And it doesn't even get into reining in emissions from China, India, etc. So yeah, I'm a pessimist.