I would say that both her and nagins inactions prior to the storm and following are responsible for the deaths and not FEMA's response.
If Blanco and Nagin had just loaded thousands of their people who had no way out onto the wasted buses of New Orleans, both city transportation and school buses, sent them up to Texas, Tennessee, Arkansas, North Carolina and a whole bunch of others and called our governors and simply said, "My people are on the way", we would have taken them in. That's the pity. That they thought so little of US. We ARE taking them in. What did they think of us? Even if the levees hadn't broken, they could have spent a few nights with us in makeshift shelters and private homes here and then went back home to N.O. Now a lot of them are here to stay.