There’s a great book that came out 20 years ago, around the time that
“JFK” by Oliver Stone came out. It’s called “JFK and Vietnam”. It makes a compelling case that, yes, Kennedy knew that South Vietnam was a lost cause, and couldn’t be made to stand on its own, and that the U.S. should cut its losses and make a stand elsewhere. His challenge was to withdraw all 16,000 U. S. advisors by 1965, all the while still looking strong and winning re-election. Those who claim that had he won re-election that 500,000 U. S combat troops would be in Vietnam by 1967, exactly the same as Johnson, are on very shaky ground, I think.