For nearly five decades, the United States has pursued a policy toward Cuba that could be described as incredibly stupid. It could also be called childish, irresponsible and counterproductive -- and, since the demise of the Soviet Union, even insane. Absent the threat of communist expansionism, the refusal by successive American presidents to engage with Cuba has not even a fig leaf's worth of rationale to cover its naked illogic. Other than providing Fidel Castro with a convenient antagonist to help him whip up nationalist fervor on the island -- and thus prolong his rule -- the U.S. trade embargo...