There is a conspiracy (I hope) to keep the po' people out of NOLA. It is called building codes.
Nagin and Blanco don't care. The city's still flooding, but they're obsessed with getting all their evacuees back. It's still hurricane season, and it's conceivable another hurricane could form and impact the gulf, but they want their people back. They can't afford to lose a single one of those votes, no matter what it costs, including lives. Do these people have a conscience? Rhetorical question.