Flooding of New Orleans could have been done by ramming a barge against the levee and that may have actually been the cause. Would Homeland Security's response been better with a no-warning terrorist barge rupture of the levee?
It should be patentedly obvious to anyone with a brain that neither DHS or FEMA or any other federal agency can possibly get to events like the flooding or 9-11 in force within anything like 48-72 hours. If you depend on the government to bail you out, you are simply setting yourself up for disappointment.