New Orleans Is Not New York
According to William Finnegan's July 25, 2005 article "Defending the City" in the New Yorker, the NYPD employs almost 50,000 people. The population of the five boroughs is over 8 million. We've heard over and over that the New Orleans Police Department had 1500 officers before it melted down. The 2000 census gave New Orleans proper a population of 484,674. If my math is right, the NYPD has sixteen times the personnel per inhabitant that New Orleans had.
(Caveat: it really would be better to compare total employed with total employed, and uniformed officers with uniformed officers to make this point more scientifically.)
It's important for people to stop using the NYPD as a benchmark to judge local responses to catastrophe. The NYPD has organized itself into something that a smaller country would call a national army: it has a foreign intelligence arm, sophisticated scientific analysts, and even a sort of a diplomatic corps. The NYPD has managed to blungeon the feds into accepting its special status, but almost no other city would be allowed to mount such an effort.
Nor would other cities be able to fund such an effort: the NYPD is funded by a local government that has given it a blank check and by a population that pays through the nose in taxes. Remember: NYC residents get a special in their NY state tax forms. I'm poor, so I don't end up paying NYC tax, but more wealthy NYC residents get hit; non-residents get hit when NYC ups the tolls on bridges and tunnels in order to avoid raising taxes on residents.
Many have made the point that during Giuliani's hour of leadership, he didn't have to work with an entire city out of commission: north of Houston, life felt strangely normal on that day, and the troops came in on the freeways. New Orleans was flooded, with transportation impossible and many communications systems down. In this radio discussion of the response to Katrina, one commenter (I think Stephen Flynn, but I'm not sure) remarked that an attack on Lower Manhattan was the only catastrophic event that could make a local official look competent. In all of the other scenarios projected, damage would be utterly uncontainable.
Despite all the reports on flooded schoolbuses, despite the stories of corruption, I tend to see Mayor Nagin as a Giuliani without resources and faced with a total collapse of the infrastructure that his office could have hoped to lead.