For this first installment of Firing Line broadcast on public television, we have as our guests two men actively seeking to dump President Nixon. Mr. Lowenstein's organization had voted in favor of impeaching him for high crimes and misdemeanors-no, not Watergate, which was still more than a year away, but rather his conduct of the war in Vietnam. For the same reason, Mr. McCloskey had announced that he would challenge the President for the 1972 Republican nomination. (As it happens, by the time of the New Hampshire primary Mr. Buckley was backing John Ashbrook for the Republican nomination-not because of Vietnam but because of President Nixon's trip to China.) A certain amount of fun & games, but then serious and deeply informed analysis of the Vietnam War itself and the history of American intervention abroad.