The Katrina disaster is real. It is not a movie. There are space, time, conflicting imperatives, poor communications, and inefficiency to contend with in addition to destruction, and flood waters, and armed gangs of desperate thugs made more desperate by the awareness that nobody is much interested in rescuing them.

Somebody was quoted on TV as asking, "Where's the cavalry?" There is no cavalry in real life. Have you never made a crucial phone call only to be told the recipient will call you back? And you wait, and wait, and wait....