Yeah that's an interesting comparison, though it's mainly b/c Vietnam sees China as its main adversary and threat, along with an opportunity to steal parts of the Asian manufacturing supply chain from China. The shared enemy and shared economic interests b/t US and Vietnam are pretty strongly aligned.

But I'm not sure if such an alignment could be created between the US and Cuba while Cuba remains a communist authoritarian hereditary dictatorship, since there's no shared enemy nearby and no strong shared economic incentive. Seems like the only real alignment would be Cuba becoming a democracy.