Depressing Theories
Bush and FEMA, as well as probably state and even local officials, managed enough damaging wrongdoing in (not) responding to Katrina, practically criminal in the case of FEMA, that we really don't need theories like this one floating around. It was apparently repeated by more than one Astrodome resident to reporter Jacob Applebaum, who is there to help set up an emergency radio station inside the make-shift Houston city. (A task that has proven to be technically simple, and beauracratically impossible) He's been taking pictures and talking to evacuees:

comments by NOLA evacuee Clara Barthelemy: "The 17th street levee was bombed by the Army Corps of Engineers to save the more valuable real estate in the city… to keep the French Quarter protected, the ninth ward was sacrificed… people are afraid to speak out… everyone who was near there heard the bombings… they bombed seven times. That's why they didn't fix the levees…"

Everything from delirium, mental instability, lack of sleep, lack of medication could lead otherwise normally thinking people into this level of paranoia. But the depressing possibility? Poor people in cities like New Orleans are really so isolated, marginalized, and uncared-for that they really just believe that the powerful are more than capable of such selfish criminality.