Chronicles the role of the United States Marines in the defense of the Pusan Perimeter and their part in the expansion of United Nations forces in the Korean War. Captain John C. Chapin earned a bachelor of arts degree with honors in history from Yale University in 1942 and was commissioned later that year. He served as a rifle-platoon leader in the 24th Marines, 4th Marine Division, and was wounded in action in World War II during assault landings on Roi-Namur and Saipan.