I'm very skeptical of this argument of yours. When has the US ever wanted to miss an opportunity, however small? It's a country 90 miles away that's near to massive American ports and has a population of 11 million people, who have hundred of thousands of their relatives living within our country. We've got great leverage and opportunity in Cuba that most other countries simply do not have.
Central African Republic, Egypt, Ukraine, China, Myanmar, Nigeria, Uganda, Saudi Arabia, Russia and Iran.
All breaking news countries with recent and egregious violations of human rights. How come we don't embargo and isolate them? The only difference is that isolation is not the status quo for these countries; that's only an incredibly limited tradition with Cuba. Quite frankly, in all other circumstances, we in the Western world seek diplomatic solutions within the country. We seek to improve the nation and empower its people through humanitarian aide and foreign investment. I simply am not sold on "isolationism" being the solution for Cuba, when we pursue complete different paths with almost all other countries.
In terms of nice beaches.
BAH! What, are you looking for a miracle? I'm about as confident in that as I am in Russia changing its national anthem to Diana Ross' "I'm Coming Out," or China dismantling its one-party state and creating a independent Tibetan state. Democratization and economic liberalization takes time; it's a rare circumstance that a government completely changes its tune and dissolves itself. Not to mention, when that does happen, it usually means flames, riots and general social unrest.
Cuba is an autocratic echo chamber. It restricts free movement, and its censorship of ideas and "dangerous" material puts China to shame. The EU is doing us liberals in the West a big one, and conditioning their negotiations on human right reforms. With trade and travel restrictions gone, it'd be an absolute boon to the Cuban dissident movement to better share information and ideas among themselves and with the larger world. I believe it is a disappointment that the US cannot bring itself to do the same.