The logical fallacy I think is yours for trying to compare Cuba to the USA in a tit-for-tat comparison of misrepresented facts and issues.
Dropping a nuclear bomb seems 'bad' until you put it in the context of what the Japanese were doing, and the costs otherwise.
The North Vietnamese that the Americans & South Vietnamese were fighting against were 10x worse than Castro (they executed 100's of thousands in the streets - and put millions in concentration camps after the Americans withdrew) - and using 'agent Orange' was an act of reasonable desperation on the part of the Americans as it was used only to clear foliage near American firebases, the casualties were mostly American and of course it was not done with the knowledge people would be hurt - the author of the note makes it seem like it was used on purpose to hurt Vietnamese which is a gross misrepresentation.
Americas role in the world is fundamentally different than that of Cuba (and of course there is the issue of scale) which makes it futile to compare the USA to Cuba, tit-for-tat in terms of 'things done'.
But the comparison is resolved rather more pragmatically:
People literally risk everything, including their lives to flee Cuba to get to America.
Never the other way around.