If you need a benchmark...
...then there's no way to call Mr. Bush's response to 911 bad or good either.
It just.... is.
In view of this, the comparison between Rudy Giuliani's behavior after 911 to Ray Nagin's after Katrina is empty too. We can't compare two responses to two incomparable, unprecedented events. We can't say that Giuliani's response was better than Nagin's, or even that Nagin's was bad. There's no precedent.
But of course, that's silly. We know what we expect of crisis management.
Surely we know, if not the expected scale of the work, what the expected quality is.