In 1718, French colonist Jean Baptiste Le Moyne de Bienville ignored his engineers' warnings about the hazards of flooding and mapped a settlement in a pinch of swampland between the mouth of the Mississippi River, the Gulf of Mexico and a massive lake to the north. Ever since, the water has sustained New Orleans and perpetually threatened it. Somehow, until this week, the mystique of the water had always washed away the foreboding of disaster, as if carrying the city's worries downstream. That was true even early Tuesday morning, when Hurricane Katrina's last-minute veer to the east convinced many residents...
