"Is it possible to make drastic cuts in greenhouse-gas emissions without destroying our economy?" asks Paul Krugman in a long magazine article looking at the economic costs and benefits associated with fighting climate change. Yes, he concludes. And while the U.S. isn't likely to take action soon, there's a good chance that continued rising temperatures will eventually marshal enough political support to further limit greenhouse-gas emissions. "We have a good sense of the costs — and they’re manageable," writes Krugman. "All we need now is the political will."