EXCERPT : The job of U.S. attorney is a political appointment. The top man in any U.S. attorney's office comes and goes. The real continuity in the office rests in the hands of scores of often anonymous assistant U.S. attorneys working there. DiBiagio had a foot planted in both worlds. Before his appointment as U.S. attorney by the Bush administration, DiBiagio worked in the Maryland office as an assistant U.S. attorney from 1991 to 2000. So he was a longtime internal operative. He's a graduate of Dickinson College, in Carlisle, Pennsylvania, and the University of Richmond, where he earned his...