As usual, the full story provides less of an outrage factor:
http://www.outsidethebeltway.com/archives/12010
He wasn't diverting resources being used elsewhere; he was already touring downtown New Orleans with a Guard escort and rather understandably wanted to see his own neighborhood a few miles away. His staff insisted he retain the escort because the area was thought to be dangerous.
After that it devolved into a comedy of errors.
I'm not sure I could have resisted the temptation to visit my destroyed house if I was within a few miles of it, though I probably would have changed my mind if the Guardsmen indicated they had more important things to do.