As Ross Douthat observed on his blog, The American Scene, Katrina was the anti-9/11.

On Sept. 11, Rudy Giuliani took control. The government response was quick and decisive. The rich and poor suffered alike. Americans had been hit, but felt united and strong. Public confidence in institutions surged.

Last week in New Orleans, by contrast, nobody took control. Authority was diffuse and action was ineffective. The rich escaped while the poor were abandoned. Leaders spun while looters rampaged. Partisans squabbled while the nation was ashamed.

The first rule of the social fabric -- that in times of crisis you protect the vulnerable -- was trampled. Leaving the poor in New Orleans was the moral equivalent of leaving the injured on the battlefield. No wonder confidence in civic institutions is plummeting.

And the key fact to understanding why this is such a huge cultural moment is this: Last week's national humiliation comes at the end of a string of confidence-shaking institutional failures that have cumulatively changed the nation's psyche.