Answer:
The Vietnam War had very noticeable effects on American society. In the first place, this conflict demonstrated the vulnerability of the United States in the military field, since until that moment America had not been defeated in this respect by any nation. On the other hand, war crimes committed by the American military, such as the My Lai massacre, caused shame in society, since they contradicted the values by which many Americans had initially supported the war. Finally, the feeling of defeat and pessimism that most Americans felt after the conflict, called the Vietnam syndrome, was a feeling of general malaise that lasted until the arrival of Ronald Reagan to the government, when American international politics took a turn and repositioned the country as one of the most powerful in the world.