Are cities more organic than we think?

Has the tragedy of New Orleans changed the way we see cities? Are they more organic than we think? And do they, in fact, go through a cycle of birth, life, and death? Is there an inevitability about it?

Babylon is gone. So is Pompeii. Venice is a shell of its former self. Prior to the Galveston hurricane, many in Texas would have thought it be the state's greatest city, not Houston or Dallas. And now we have question if New Orleans can come back.

Do you believe in this day and age, short of a natural or man-made catastrophe, that a city can literally "die"....basically come to the end of its existence because there no longer is economic opportunity there?

Are our great cities far more temporary than we would like to believe?>