Foreign relations of Cuba needed oil. Relations between the countries deteriorated rapidly. In April 1961, following air attacks preparing for the Bay of Pigs Invasion by CIA-trained Cuban exiles, prime minister Fidel Castro declared Cuba to be a socialist republic, and moved quickly to develop the growing relations between Cuba and the Soviet Union. In 1962, Cuba was expelled from the Organization of American States. Shortly afterwards, many nations throughout Latin America broke ties with Cuba, leaving the island increasingly isolated in the region and dependent on Soviet trade and cooperation. Following the establishment of diplomatic ties, and after the Cuban missile crisis in
CIA activities in Vietnam had difficulties understanding their politics. This can be attributed to the fact that the CIA did not make a concerted effort to gain a better understanding of the history and people of Vietnam. The CIA instead focused on the military forces occupying the territory instead of the political and economic forces that motivated them. The diplomats were not getting clear information in 1954 and early 1955, but the CIA station "had ... no mandate or mission to perform systematic intelligence and espionage in friendly countries, and so lacks the resources to gather and evaluate the large amounts of information required