There is discussion that a video of a FEMA briefing supposedly proves that President Bush had been warned that the levees in New Orleans could be breached. If you listed closely to the briefing, they talk about the levee being "topped."
Click here for a discussion of "topped" vs. "breached." As I understand it, a levee being topped means that you have to pump out the water that spilled over, but the levee is still sound enough to keep the rest of the water out of the city. This "topping" would be like spilling some coffee from your cup into the saucer. A breach, on the other hand, means that the whole coffee cup is broken and the coffee suddenly spills everywhere.
When the storm turned out not to be a category 5, it seemed reasonable that the levees would hold. So the President's assertion that no one predicted the breach is not contradicted by the video.
Am I missing something here?