For six decades, Seymour Hersh's reporting for such publications as The New York Times and The New Yorker has changed public opinion and government policy – from documenting the My Lai massacre during the Vietnam War, to uncovering torture by American service members at the Abu Ghraib prison in Iraq. "60 Minutes" correspondent Lesley Stahl talks with the Pulitzer Prize-winning journalist about his career exposing corruption, and where he believes America stands now. She also talks with Laura Poitras, co-director of a new documentary on Hersh, "Cover-Up," about putting the reporter with a reputation for crankiness on camera.