Address. An address for the 1982 John XXIII Lecture. Two copies. ~ The trend of CO's in the Vietnam War are due, at least partially to John XXIII's address of 1963, "Peace on Earth." Zahn explains that the violence of war, and the killing, comes down to hte actions of the individual, not the leaders. Zahn suggests that it is the individual's responsibility to end war by not participating.