Detroit Mayor Dave Bing greets President Barack Obama upon his arrival at Detroit Wayne County Airport in Detroit, Friday, July 30, 2010. At right is Rep. Carolyn Kilpatrick, D-Mich. (AP Photo/Pablo Martinez Monsivais)

Photo by: Pablo Martinez Monsivais

Detroit Mayor Dave Bing greets President Barack Obama upon his arrival at Detroit Wayne County Airport in Detroit, Friday, July 30, 2010. At right is Rep. Carolyn Kilpatrick, D-Mich. (AP Photo/Pablo Martinez Monsivais)