While President Bush says he will respect the conviction of Lewis "Scooter" Libby on four felony counts of perjury and obstructing justice earlier this week, conservative allies already have begin a campaign to secure him a presidential pardon. Vice President Cheney's former chief-of-staff has been one of the most trusted members of the White House inner circle. But it might not be so easy for Bush to grant such a pardon, says Newsweek investigative correspondent Michael Isikoff.