On more than 30 occasions, the United Nations Assembly has discussed the blockade against Cuba, which costs the island 5 billion dollars annually, according to some estimates. Every year the resolution is proposed and the whole world, through the vote of the absolute majority of the member countries of the United Nations General Assembly, has condemned the imperialist attitude of the United States towards Cuba.
Why is it normalized that one country can block/embargo/complicate/whatever-you-want-to-call-it another country to the point of severely affecting the lives of millions of people .... for what? because one country disagrees with the politics of another country?
If countries were able to do that, there would be no trade anywhere in the world.
Yet it's been completely normalized for the past six decades between the US and Cuba.
Countries have complicated trade for centuries. Free trade is a modern exception, not the historical rule.
And in principle, countries have as much right to restrict trade with Cuba as they do with Russia and Israel. It's the same principle that allows people to call for boycotts of Amazon and Starbucks. All of these things can affect the lives of millions, in an effort to bring about political change.