You forgot:
11. Lousiana and Mississippi's completely unreasonable unwillingness to enforce house and building codes (or have ones to begin with). They are unwilling to change this even in the face of unmitigated disaster! Pressure from Real Esate Agencies and Building Contractors gets the elected officials to back down.
http://159.54.227.3/apps/pbcs.dll/article?AID=/20050829/NEWS/50829030612. The indiference factor plays a big part. They knew for decades that the flood protection system was bound to fail. No initiative or money for that (of course we'll pay 100 times as much now because it's needed overnight). Nice foresight! I think those in charge must drink as often and as much as their tourists.