This episode's headline: In Retrospect; Healing the Wounds?; Affirmative Action. The guests include ROBERT McNAMARA, Former Secretary of Defense; GEORGE McGOVERN, Former Democratic Senator; SEN. JOHN McCAIN, [R] Arizona; ROBERT SCHEER, Former Editor, Ramparts Magazine; McGEORGE BUNDY, Former National Security Adviser; RUTH SIMMONS, President-Elect, Smith College; CORRESPONDENT: CHARLAYNE HUNTER- GAULT. Byline: In New York: ROBERT MAC NEIL; In Washington: JAMES LEHRER