1) The Federal Gov't doesn't build levees they contract the building of levees. If flood protection was a priority the levee system shouldn't have been designed to CAT3/4, but N.O. from a political perspective isn't much of a priority on the national level nor is the majority of the improvised residents. The gov't doesn't put out minimum contracts to secure Ft. Knox, butt then again that is a priority of theirs.
2) The Federal Gov't doesn't maintain levees. That is the responsibility of individual levee boards.