People protested the Vietnam War because they felt that it went against everything the U.S had worked for.
To respond to the quote, " For many Americans, the enduring memory of the Vietnam War is of the protests that defined a generation and shattered the illusion of America's purity on the world stage. But for the 3 million men and women who served in Southeast Asia in the 1960s and early 1970s, the memories are more visceral: the fog of combat, the stench of death, the sting of returning to a seemingly ungrateful nation." Many Americans remember the protest more than anything else because the protests were something that everyone could relate to. The everyday person did not know what it was like to fight in Vietnam, so they could not relate to that side of the Vietnam War. For those who did serve, they had more of a passion because they could see both sides of the war and why it was unwanted.