As a rule, the press is the scourge of presidents. They’re expected to endure unending scrutiny, mistrust, and badgering—plus hostility if they’re Republicans—by a hectoring herd of reporters and commentators in the mainstream media. But there’s an exception to the rule: President Obama. It’s counterintuitive, but Obama has been hurt by the media’s leniency. Both his presidency and reelection prospects have suffered. He’s grown lazy and complacent. The media have encouraged him to believe his speeches are irresistible political catnip, though they aren’t. His overreliance on words hasn’t helped. The kind of media pressure that can cause a president to...