On this edition of Your Call, we’ll discuss The Movement and the “Madman,” a new PBS documentary that shows how two antiwar protests in the fall of 1969 — the largest the country had ever seen — caused President Nixon to cancel what he called his “madman” plans for a massive escalation of the U.S. war in Vietnam, including his threats to use nuclear weapons. The filmmakers say at the time, protestors had no idea what they had prevented and how many lives they had saved. The Movement and the “Madman” is airing now on PBS.