“The bad news,” investigative reporter Seymour Hersh told a Montreal audience last Wednesday, “is that there are 816 days left in the reign of King George II of America.” The good news? “When we wake up tomorrow morning, there will be one less day.” Hersh, a Pulitzer-prize winning journalist and regular contributor to The New Yorker magazine, has been a thorn in the side of the U.S. government for nearly 40 years. Since his 1969 exposé of the My Lai massacre in Vietnam, which is widely believed to have helped turn American public opinion against the Vietnam War, he has...