As I write these words, the season’s first named storm—Alberto—is developing in the Caribbean. We’re now in what everyone refers to as hurricane season, which is joining winter, spring, summer, autumn, Christmas and football as a fixture on the calendar. (It probably has a brighter future than winter.)A few years ago, words like these would have been scoffed at by most mainstream Americans, treated as the unlikely emanations of radical greens. (Trust me on that.) But within the past year or so the tide has turned. Katrina had something to do with that. So did Al Gore.