That said, i don't think sanctions violate intl law. You are under no obligation to trade with people you dont like. A blockade probably would be (generally blockades are an act of war which is only allowed in defense or if un security council approves) however america isnt blockading it.
International law isn't real. You can tell it's not real because if it were real there would be real repercussions for violating it. There aren't, so it isn't. It's just words made up for politicking and persuasion.
That said, i don't think sanctions violate intl law. You are under no obligation to trade with people you dont like. A blockade probably would be (generally blockades are an act of war which is only allowed in defense or if un security council approves) however america isnt blockading it.
Things can morally wrong without being illegal.