In the 1950s, North Vietnam was ruled by an enigmatic dictator named Ho Chi Minh. His government was supported by the Communist nations of China and the Soviet Union, and China exerted a heavy influence on North Vietnam's affairs of state. The leader of South Vietnam, Ngo Dinh Diem, had weak support from his people, but was supported by the United States. Although Diem had pledged to hold democratic elections, he continued to resist such measures.

Within South Vietnam, Communists organized resistance to Diem's policies, which favored a small minority of land owners over a poverty-stricken populace. By the time Diem was overthrown in 1963, the North Vietnamese Communists, called Vietcong, were firmly entrenched within dozens of South Vietnamese villages.

In 1964, President Lyndon Johnson used the small skirmish in Vietnam's Gulf of Tonkin as an excuse to declare war against North Vietnam. The United States originally...