its sad, but thats the chance you take by living on the Gulf Coast and the Mississippi delta. Same way people who live in florida take chances by living in a hurricane target area, or people in Cali facing earthquakes, mudslides, forest fires, or people along the mississippi (or other rivers) that could face flooding.
Scientists have been saying New Orleans has been a sitting duck waiting to get hit. They've been lucky up until this point that they haven't. NO should have been better prepared for this. How are you not going to be prepared when your city is surrounded by water, and in fact has a below level elevation? Someone is going to pay for this, and rightly so, whether it be the mayor or governor for not preparing the city, or the president who cut funding for levee repairs by 44% before this happened.