2.5 million people evacuated Houston, and in record time, even though Houston was spared the full brunt of the hurricane. The bottomline is, the mayor of Houston issued the mandatory evacuation order at the right time, and the good people of Houston heeded the warning when it was issued.
Blanco and Nagin, given a second chance to redeem their stupidity, failed yet again, because they were purely driven by sheer emotion, while the public officials in Texas were calm, cool, and collected in the face of incoming danger.