This episode's headline: Politics of War; '92 Election - Making His Case; Prescription for Change. The guests include DR. MICHAEL ISIKOFF, Radiologist; JAMES WEBB, Author; MICHAEL MANDELBAUM, Political Scientist; SEN. JOHN McCAIN, [R] Arizona; JAMES FALLOWS, Atlantic Magazine; PATRICK BUCHANAN, Republican President Candidate; DR. MICHAEL ISIKOFF, Radiologist. Byline: In New York: ROBERT MacNeil; In Washington: JAMES LEHRER