Correct me if I am wrong (I'm sure you will), but the last I checked there is no blockade of Cuba. There are trade and travel embargoes on Cuba, but there is nothing illegal about that, nor can you stretch that to claim it is immoral. I'm not really sure I would call it brutal. Cuba is free to trade with every other country in the world. What we won't give them you would think they could manage to get from others.
Admittedly, the US embargo has had and will continue to have an effect on the Cuban people. That is the point of any embargo, to create economic hardship that the Cuban government would have to respond to in such a way as to cause the US to ease the restrictions. Thus far the Cuban government seems not to care about doing so, thus the embargo continues.
With all this misery you claim the US has caused the Cuban people, you would think they would really hate us, and yet many of them keep trying to get to our shores. Go figure.