Before 9/11 the Federal Emergency Management Agency listed the three most likely catastrophic disasters facing America: a terrorist attack on New York, a major earthquake in San Francisco and a hurricane strike on New Orleans. "The New Orleans hurricane scenario," The Houston Chronicle wrote in December 2001, "may be the deadliest of all." It described a potential catastrophe very much like the one now happening.

So why were New Orleans and the nation so unprepared? After 9/11, hard questions were deferred in the name of national unity, then buried under a thick coat of whitewash. This time, we need accountability.

First question: Why have aid and security taken so long to arrive? Katrina hit five days ago -- and it was already clear by last Friday that Katrina could do immense damage along the Gulf Coast. Yet the response you'd expect from an advanced country never happened. Thousands of Americans are dead or dying, not because they refused to evacuate, but because they were too poor or too sick to get out without help -- and help wasn't provided. Many have yet to receive any help at all.

There will and should be many questions about the response of state and local governments; in particular, couldn't they have done more to help the poor and sick escape? But the evidence points, above all, to a stunning lack of both preparation and urgency in the federal government's response.