Alongside everything else that can be said about Hurricane Katrina, Dennis Hastert of all people asks the offensive-but-important question: Should New Orleans even be rebuilt? No, really. Looking at this New York Times article drives home the point that this man vs. nature fight going on in the Mississippi Delta will ultimately be won by nature. The patchwork of dams and levees erected alongside the river over the years have prevented much-needed sediment and other minerals from being deposited on much of the land, including the area on which New Orleans sits. As a result, the riverbed and lake keeps rising, while the city keeps sinking further and further down into the ground. And diverting the river has allowed salt water from the Gulf of Mexico to erode the wetlands of southern Louisiana, crumbling the state away into the sea.

How much longer is this sustainable? Maybe Hastert's right; maybe it would make more sense to take this opportunity to just pack up and move the whole city somewhere else; because it's ultimately unsustainable, and nature is going to work faster to attack the city than the labyrinth of city boards and councils will work to defend it.

On the other hand, how feasible is packing up and moving a whole city? Not very, I would imagine. As far as the region goes, the oil and gas interests that dominated the southern shoreline make it unlikely that people are ever going to surrender that land back to nature. Not in this lifetime, no matter how many catastrophes occur. New Orleans itself, meanwhile, is the "largest faction of the Port of South Louisiana, [the] largest and busiest shipping port in the Western Hemisphere." So as satisfying as it might be to ridicule New Orleaners for continuing to live in a city that sits, essentially, on shifting mud, there doesn't seem to be much of a choice here. Not to mention, obviously, the cultural and physical attachment that hundreds of thousands have to the place itself.

More practically, though, I wonder what will be left of the city once the devastation clears away. A variety of people are going to have to leave the city for months on end, maybe years. What will they do? What happens to their jobs? If they can get by on their savings, and the kindness of family members, good for them. If not—if, say, you live paycheck to paycheck and need a job immediately, well, you're going to need to go to some other town, find work, get an apartment or place to live, and stay there for those intervening months. By the time New Orleans is inhabitable again, how many people will actually drift on back?

UPDATE: On the last topic, a Wall Street Journal article today notes that, historically, cities do tend to rebound after natural disasters, and their populations tend to return to pre-catastrophe levels. Okay, but consider this: Between 1960 and 2000, the population of New Orleans declined some 23 percent. People have been leaving for a long time. Katrina may just accelerate that exodus.