This book looks at the Air Force's support of the ground war in South Vietnam between 1965 and 1968. The book covers the period of time when the United States began moving from an advisory role to one of active involvement to just before the time when the United Stated gradually began disengaging from the war. The final scene is the successful air campaign conducted during the Communists siege of the Marine camp at Khe Sanh. While the actual siege lasted from late January to the middle of March 1968, enemy preparations for the encirclement were seen as early as October 1967.