Today's papers are reporting that Homeland Security Secretary Michael Chertoff is being castigated by Senators for the "late, uncertain, and ineffective" government response to Hurricane Katrina. It is quite possible that Chertoff could have been more on the ball, but I suggest that a larger factor was the fact that Homeland Security is an enormous, cumbersome bureaucracy.
Consider that, in the case of Katrina, Homeland Security was dealing with an "enemy" that announced the general time and location of its "attack" days in advance, and that the form the assault would take was known and well understood. Katrina made no attempt to deceive or misdirect officials, nor did it study the likely defences in an effort to work around them.
Human enemies are unlikely to be so considerate. If Homeland Security could not do an adequate job coping with a threat like Katrina, what are the odds it will do better when faced with an intelligent, scheming foe?