By Fred Burton Editor's Note: The following piece is part of an occasional series in which Fred Burton, our vice president of intelligence, reflects on his storied experience as a counterterrorism agent for the U.S. State Department. After decades of hostility, the United States and Cuba finally seem to be reconciling. On July 1, U.S. President Barack Obama announced that Washington will reopen its embassy in Havana. For the first time since 1961, when the two countries severed ties, U.S. diplomats and staff will fill the embassy and the surrounding city streets, as will a U.S. Marine detachment working security detail. But even as the embassy in Havana now stands as a monument to improved U.S.-Cuban relations, it will make the United States much more vulnerable to monitoring and infiltration by Cuban intelligence agencies.