[iron81]

If you guys want to do a Constitutional argument, the combination of the Supremacy clause, the Commerce clause and Congress's power to levy tariffs should make it clear that the Feds have power over foreign trade.

As far as the reason for the embargo, yes the Cuban immigrant community is largely responsible. However, this is beginning to change. The 2nd generation of immigrants that really has no knowledge of Cuba largely opposes the embargo and polling shows that only half of the Cubans support the embargo. Obama likely picked up on this which is why he's the first major candidate that I'm aware of that proposes loosening the embargo. Its just that the embargo supporters control the organizations, are the loudest and donate the most money.

Edit: I just looked and the Constitution specifically says Congress shall have the power to regulate trade with foreign nations.