You are missing the point, America had kept it’s distance from Vietnam although we had a handful of men there under FDR, Truman, and two terms of Eisenhower, and the French defeat, and then suddenly BOOM, JFK sends in 16,000 troops and contributed to Diem being killed, he was starting his war, and he did.
No JFK, no Vietnam war, JFK was a boob, more like Jimmy Carter, except perhaps worse, even his war heroics was something that he should actually have faced courts martial on, instead, like everything with JFK, his failure and incompetence is flipped into the opposite.
You will have to scroll down for the Reagan letter to Nixon.
https://faculty.washington.edu/qtaylor/Courses/101_USH/101_manual_9.htm
“No JFK, no Vietnam war,”
I think that’s overstating it. The Communists had a vote in all of this. They ramped up their insurgency around the time Kennedy took office and he either had to increase our aid to Vietnam or let them get overrun. My dad’s office partner was the Army’s small arms expert and by fall 1961 he was saying “they may not call it a war but they are sure using ammunition like it’s one”. The pace of war was picking up very quickly in Kennedy’s first year.
I do put a lot of blame on Kennedy for getting Diem killed and leaving a chaotic mess behind. Ho Chi Minh couldn’t believe his good luck. Diem’s assassination played a big role in Johnson’s decision to have the US military take charge of ground combat in the war.
“JFK was a boob, more like Jimmy Carter, “
I wouldn’t put them in the same category. Carter was naive, whereas Kennedy was reckless and that’s a dangerous enough quality in an American President.