I don't think he's trying to turn Cuba into Vietnam, I think the comparisons don't reach beyond an earlier anti-war movement, (which was already nascent within the beatnik culture). US forces aren't bogged down and the opposition is fractured.I really hope you don't try to turn Cuba into a Vietnam for this timeline; it lacks a lot of what made the latter what it was. Biggest reason is distance and logistics; it's proximity makes it harder for commie funding and easier for the US to go through too. Also smaller and more of a pain for guerrilla warfare on the defender's part.
This would not be the war I'd use for that; an African war would probably be more effective if you need the anti-war theme to ooze in as it did for us.