Not so much from a personal experience sort of desire, but I think we get socially complacent and come up with silly ideas about how to live, and every once in a while a good dose of reality needs to come up and bite us just a bit and let us know how things really are. I don't advocate apocolyptic extremes, but Katrina was a good sort of wake up call for many people, not just those who were directly affected by the storm. It should never have gotten as bad as it did, and thankfully it was not nearly as bad as it could've been.

A little exposure, just like a little revolution, now and then is a good thing.