What happened shortly after the United States left Vietnam? The North Vietnamese retreated. North Vietnam kept Communism out Sou
th Vietnam permanently. North Vietnamese took over South Vietnam, spreading Commonunism southward. Vietname agreed to leave South Vietnam in sixty days.
The answer is the North Vietnamese took over the South Vietnam spreading communism Southward and this proved the domino theory (if one country come under the influence of communism, the surrounding countries would follow).
