Grist: Im driving down a dirt road in the vast tangle of coastal bayous that stretch south of New Orleans, so that Reggie Dupre can show me his pride and joy. This is the little silver lining on the very dark cloud that was over Louisiana, he says. In front of us, construction crews are shaping mounds of rock and dirt into a mile-long, 12-foot levee. On one side is a canal, crammed with boat traffic for the offshore oil drilling industry. On the other side is Terrabonne Parish, a rural community of...