In fact, once you filter out the noise generated by special-interest groups, you discover that there is widespread agreement among environmental economists that a market-based program to deal with the threat of climate change—one that limits carbon emissions by putting a price on them—can achieve large results at modest, though not trivial, cost. There is, however, much less agreement on how fast we should move, whether major conservation efforts should start almost immediately or be gradually increased over the course of many decades.

Prior to consideration of the more detailed economic issues—e.g., costs versus benefits of attempts to forestall the problem; the danger of worse-than-expected outcomes, etc.—pause to recognize that according to the IPCC the expected economic costs of global warming under the plausible scenarios for future economic growth are likely to be about 3 percent of GDP more than 100 years from now. This is pretty far from the rhetoric of global destruction and Manhattan as an underwater theme park.

True, a 3 percent drop in global GDP may not sound so bad. We'll all be much richer in 2100, we can take a hit. But that top-line figure can obscure some serious distributional issues. Climate change, after all, is expected to hit developing countries much harder than wealthier ones. And as Nate Silver once noted, you could completely wipe out the poorest 81 nations in the world, with a total population of 2.8 billion, and the blow to global GDP would "only" be about 5 percent.

Like the attacks by Al Qaeda, the disaster in the Gulf was preceded by ample warnings—yet the administration had ignored them. Instead of cracking down on MMS, as he had vowed to do even before taking office, Obama left in place many of the top officials who oversaw the agency's culture of corruption. He permitted it to rubber-stamp dangerous drilling operations by BP—a firm with the worst safety record of any oil company—with virtually no environmental safeguards, using industry-friendly regulations drafted during the Bush years. He calibrated his response to the Gulf spill based on flawed and misleading estimates from BP—and then deployed his top aides to lowball the flow rate at a laughable 5,000 barrels a day, long after the best science made clear this catastrophe would eclipse the Exxon Valdez.