For starters, how the fuck do you enforce an embargo without the threat of violence, and secondly I love how me and all my communist friends are expected to have a PhD in world history and economics while your average liberal can cite two state department links and a CIA funded NGO and call it a day.
It's actually just America asking very nicely that nobody else trade with Cuba. Everyone just likes America so much, because America is so wholesome and kind, that they oblige. Even the Cubans oblige. Nope, no threat of military intervention at all! That military budget is actually just like a funny little inside joke you wouldn't understand.