15867. WHY THE U.S. BECAME INVOLVED IN THE VIETNAM WAR. This paper argues that the U.S. entered the Vietnam War because of unrealistic concerns over Communist expansion, and remained in the war in order to maintain credibility in the eyes of the world. In the end, the nation failed to meet its objective of stopping a communist takeover in South Vietnam. KEYWORDS: vietnam war term paper. 8p., 16f., 4b.