Lowry on the levees, MRGO, and the floodwalls

From "What caused the flood? Take your pick":

The ''more funding for levees'' argument perpetuates a common misperception. The long-standing earthen levees surrounding the city did not fail. It was the floodwalls around the drainage canals that protrude into New Orleans that were overwhelmed. One breach seems to have been caused by a barge breaking loose from its moorings and battering down one of the walls. Will Nancy Pelosi now accuse Bush of underfunding barge moorings?
...In fact, the section of 17th Street canal where a major breach occurred had just been upgraded, and The New York Times writes ''received more attention and shoring up than many other spots in the region.'' Even if Bush had larded more money on New Orleans - according to a broad-brush comparison in The Washington Post, he spent more in his first five years in office than Bill Clinton did in his last five - it wouldn't have stopped such a breach...
...The Washington Post reports that only 3 percent of the port's cargo comes through the [Mississippi River Gulf Outlet], at a price to taxpayers of an estimated $12,000 per vessel. Still, the U.S. Army Corps of Engineers spent $13 million dredging the canal last year. Even though there were warnings about the dangers of MRGO, even though it was commercially marginal, the Corps wanted to spend up to $38 million on keeping it going...