What American city needs to "start over" the most?

There are some American cities that have gone so far into a pit of self-destruction and despair that some may even proclaim, "we might as well start over!" Some cities may even be somewhat healthy but have a major flaw in their design that just prevents them from reaching their full potential. However you view it, lets ask the question: which American city, if possible, would benefit the most from starting ALL over with a clean slate? This is assuming, of course, that plenty of money and interest would exist to actually rebuild the city from scratch.>