Renowned scholar of Cuba Louis A. Perez Jr. makes the case at CNN.com for an end to the failed U.S. policy of embargo against Cuba. He begins: In April 2009, the White House released a presidential memorandum declaring that democracy and human rights in Cuba were "national interests of the United States." Assistant Secretary of State Arturo Valenzuela repeated the message in May of this year to the Cuban-American National Foundation in Miami. The Obama administration, he said, wanted "to promote respect for human rights and fundamental freedoms ... in ways that will empower the...