You make one good point
There is no rational reason for trading with other oppressive regimes while cutting Cuba off.
The rest of your post is a bit inane.
Oh, sure, Cubans have better human rights than Americans. I can tell by all the cartoons down there that display Castro as a chimp.
And as always, you horribly underestimate the amount of control a ruthless minority can maintain over a large number of people. The idea that if a nation's people aren't rising to overthrow their oppressive leaders, then they must support them, is ridiculous.