Jones (Mutiny on the Amistad) delivers an informative narrative documenting in rather elaborate detail a popular theory of JFK and Vietnam advanced previously by such writers as Richard Mahoney and Richard Reeves: that had Kennedy lived, U.S. involvement in Vietnam would not have escalated as it did. There were 685 U.S. advisers in Vietnam on the day Kennedy was inaugurated president in early 1961. Less than three years later, in October 1963, the U.S. had 16,732 American troops in place. Despite this escalation, Kennedy was never wholly convinced of the wisdom of American involvement in Vietnam. Minutes of the September 6, 1963, National Security Council meeting, two weeks after Kennedy gave the go-ahead for the overthrow of South Vietnamese president Ngo Dinh Diem, show Robert Kennedy openly questioning whether Communist takeover of the South could be successfully resisted, regardless of whether Diem remained in place or not. The president himself is on record even earlier, in April 1962, as telling his aides to "seize upon any favorable moment to reduce our involvement." Hawks such as Dean Rusk in Kennedy's cabinet (shortly inherited by LBJ) did not agree. Jones, like most scholars in recent memory, argues that the instability of Diem's government, followed by the assassinations of Diem and JFK, combined to create an environment where escalation of American involvement in Vietnam became inevitable, thus triggering what Jones terms "the death of a generation." Although not advancing an original thesis, Jones, a historian at the University of Alabama, goes deeper into the existing evidence supporting this thesis than have most other writers, and does so in a highly readable manner. (Mar.)