When he was trying to win the Vietnam War, Richard Nixon famously told his chief of staff that he wanted Communist leaders—in the Soviet Union, in North Vietnam—to think that the U.S. president was a mad man, that he was capable of doing pretty much anything up to and including the use of nuclear weapons. Fear of an unpredictable, erratic leader would bring the Communists to the negotiating table and render them more conciliatory.
Nixon’s was, of course, a calculated craziness. “When the wind is southerly,” Tricky Dick certainly could distinguish “a hawk from a handsaw,” as Hamlet famously put