REVISED EDITION: Gaining a firm grasp on the highly complex, famously fraught aftermath of Hurricane Katrina can seem as tenuous as its victims' shaky grasp on survival. Mayor C. Ray Nagin was there during the city of New Orleans' darkest hours. Charged with assessing the forces that swirled around him, the city's leader strove to maintain formidable calm in the face of the biggest natural and man-made disaster in America's history. That is, until he simply could not. Nagin's first-hand account, Katrina's Secrets: Storms after the Storm lays out the days leading up to and immediately...