For years, Hoover had been worried—or obsessed—by King, viewing him as a profound threat to national security. Hoover feared that the communist conspiracy he was committed to smashing whether it was a real danger or not was the hidden hand behind the civil rights movement and was using it to subvert American society. He was fixated on Stanley Levison, an adviser to King who years earlier had been involved with the Communist Party, and in 1962 the FBI director convinced Attorney General Robert Kennedy to authorize tapping the business phone and office of Levison, who often spoke to King. Then Hoover, as Tim Weiner puts it in his masterful history of the FBI, Enemies, began to “bombard” President John Kennedy, Vice President Lyndon Johnson, Bobby Kennedy, and leading members of Congress with “raw intelligence reports about King, Levison, the civil rights movement, and Communist subversion.” Hoover’s priority mission was to discredit King among the highest officials of the US government. Though King scaled back his contacts with Levison—after both RFK and JFK warned King about associating with communists—Hoover kept firing off memos, Weiner notes, “accusing King of a leading role in the Communist conspiracy against America.”The August 1963 march, which captured the imagination of many Americans, further unhinged Hoover and his senior aides. The day after the speech, William Sullivan, a top Hoover aide, noted in a memo, “In the light of King’s powerful demagogic speech…We must mark him now, if we have not done so before, as the most dangerous Negro of the future in this Nation from the standpoint of communism, the Negro, and national security.” Six weeks later, pressured by Hoover, Bobby Kennedy authorized full electronic surveillance of King. FBI agents placed bugs in King’s hotel rooms; they tapped his phones; they bugged his private apartment in Atlanta. The surveillance collected conversations about the civil rights movement’s strategies and tactics—and also the sounds of sexual activity. Hoover was enraged by the intelligence about King’s private activities. At one point, according to Weiner’s book, while discussing the matter with an aide, an irate Hoover banged a glass-topped desk with his fist and shattered it.