Be angry. Be very angry.
Don't let yourself be conned by the Right, who says that now is not the time to point fingers. They're pointing their own fingers at the hard-working and underfunded local New Orleans authority. The central blame for the severity of the aftermath (remember, be very careful to indicate that you're not blaming anyone for the hurricane itself--that's another Straw Man from the Right) lies on the heads of the Republicans in power in Washington, both now and during the Reagan era.
Don't let yourself be conned by the Right, who says that they didn't know this was coming. Bush says that no one expected the levees would be breached. That, folks, is just a big fat lie. I strongly encourage you to take a look at the extensive reporting done by Daily Kos member Federalist, who is right on the money even if he isn't a meteorologist. Be sure to look at the "Hurricane 'Pam'" simulation run by FEMA in 2004. The link is in the Federalist post, near the top.
It is not "playing politics" when we hold this wretched administration responsible for the dereliction of duty displayed during this last week. There is no "play" about it. The Republicans' deliberate indifference to certain American lives is deadly serious.