It taught most of the world to be sure why one invaded another country and not to under-estimate your enemies. The U.S. lost a president over it JFK and Bobby Kennedy (partly the reason for their assassinations.) It made the American people realize for the first time they had a say in a war that was wrong (first time in history) and that they indeed could do something about it and they did! It showed the world that soldiers are dear to our hearts (they do the dirty work for us) they are our sons, brothers, husbands and that to mislead them into a useless war, using them as guinea pigs (Agent Orange and Agent White) was wrong and that not only America, but many other countries (Canada for sure) couldn't trust their governments. That Propaganda was the devils play ground and most of it was untrue and caused many families and friends great angst and sometimes divisions between each other over the war. It also showed the world that these soldiers (if they made it home) came back with not only broken bodies, but broken minds and were insulted beyond comprehension and called "baby killers." They thought they were serving their country and it was the first time in American history where many of the people of the country turned their backs on their own boys! They had difficulties finding work, some were hooked on drugs, many had psychological difficulties (to this day.) The soldiers had to try and come to grips with the fact they not only risked their own lives, but saw many of their friends killed in this war which was being called "a mistake!" War is hell at best. I believe the worst slight given to the American soldiers was not being recognized for protecting their own country right or wrong. There was a fight over the "black wall" with the names of dead soldiers (at one point there was a fight going on that black soldiers were not to have their names on that wall, but thanks to many black/white alike their names were put on the wall) and instead of the American Government admitting the war was a mistake (they lost) they tried to hide and lie their way through it and little history given for future generations to learn from. I went into a war museum on the Oregon Coast and I was shocked to see that of all wars displayed and the Vietnam War was not. I went right to the Curator (a woman) and asked why. She went red-faced and quietly said, "Isn't it a shame." You bet it's a shame! My husband and I were disgusted! War is hell at best and from each war we should learn something from it. War unfortunately is inevitable in this world, but governments should be far more careful how and where they chose their wars and come to realize that the people of the U.S., Canada or any other country are bright individuals and need to know the truth.