"Katrina is about the sudden and complete loss of all that home means—safety, respite, privacy, comfort and security.” On a chilly autumn night, Jocquelyn Marshall opened the door to her new home, an apartment tucked in a maze of quiet streets lined with townhouses south of downtown New Orleans. She’d been here only two weeks since making it back from Houston, and the newly-built, two-bedroom apartment was sparkling but almost completely bare. She sat on a milk crate in the middle of the hardwood living room floor, while her 12-year-old son, Justin, watched television on the white carpet in his...