What was the outcome of the Vietnam War? Why was the Vietnam War important?

The final outcome of the Vietnam War was that North and South Vietnam were united under the Communist North in 1975 despite the best efforts of American servicemen who left the area following the Treaty of Paris in 1973.  The Vietnam War was important politically because it demonstrated that America would fight against Communist aggression.  However, it also proved that American traditional warfare was not prepared to fight against insurgencies and no matter how many bombs were dropped and how much herbicide was deployed in North Vietnam, America could not win against a determined enemy fighting on his own native soil.  The Vietnam War also helped to further destabilize governments in Laos and Cambodia and led to one of the largest genocides the world has ever witnessed.  The aftermath of the Vietnam War also created a refugee crisis as people who supported the South Vietnamese government left to get away from North Vietnamese attack.

Domestically, Vietnam was important because it created a rift between people and government as the White House told the American people that the Communists were losing but the Tet Offensive of 1968 proved otherwise.  The Vietnam War also led to the 26th Amendment giving 18-year-olds the right to vote in elections--this was important as this same group of young people was also being called upon to be drafted into the war.  After Vietnam, American military forces are now volunteers, though young men still have to register for the draft.  America was hesitant to send more troops into harm's way, and there are some that still use "Vietnam" as a synonym for military quagmire.