Hours before they were to leave office after eight troubled years, George W. Bush and Richard B. Cheney had one final and painful piece of business to conclude. For over a month Cheney had been pleading, cajoling, even pestering Bush to pardon the Vice President's former chief of staff, I. Lewis (Scooter) Libby. Libby had been convicted nearly two years earlier of obstructing an investigation into the leak of a covert CIA officer's identity by senior White House officials. The Libby pardon, aides reported, had become something of a crusade for Cheney, who seemed prepared to push his nine-year-old relationship...