Havana is only 90 miles from Florida, but to get here we had to travel a great distance -- over barriers of history and ideology; barriers of pain and separation. The blue waters beneath Air Force One once carried American battleships to this island -- to liberate, but also to exert control over Cuba. Those waters also carried generations of Cuban revolutionaries to the United States, where they built support for their cause. And that short distance has been crossed by hundreds of thousands of Cuban exiles -- on planes and makeshift rafts -- who came to America in pursuit of freedom and opportunity, sometimes leaving behind everything they owned and every person that they loved.