Dang straight! But you'd rebuild the city underwater? Scum would just float again. Raze it, increase the elevation upon its waste, make a smaller more modern and efficient city.
My heart goes out to all those who've lost everything, yet that same heart is twisted by the breakdown in civilization from affected groups.
Think about what is to become of that "scum" as you put it. Coming to a city near you? Of course, a city near you already has a number of them, but there hasn't been a disaster (aka looting opportunity) to bring them out of the woodwork into the full light of the day--and teevee cameras.
Meanwhile the many decent and good people of New Orleans deserve to have their city rebuilt, just as they rebuild half of the east coast after their yearly hurricane season, and the west coast, after their yearly wild fires and mudslides.