Thomas Jefferson looks on nervously while Lyndon Johnson “confers” with Sen. Richard Russell (D-Ga.). At 6’4″, Johnson tied Abraham Lincoln as the tallest U.S. president, and he used his physical presence to advance his agenda, cornering his targets in out-of-the-way places and leaning “so close to you,” one staffer recalled, “that your eyeglasses bumped.” In their 1966 book The Exercise of Power, Rowland Evans and Robert Novak dubbed this The Treatment: The Treatment could last ten minutes or four hours. It came, enveloping its target, at the Johnson Ranch swimming pool, in one of Johnson’s offices, in the Senate cloakroom,...