The US had an infamous history of military intervention in Latin America after establishing its hegemony over the western hemisphere. In 1895 it tacitly encouraged Britain to cede territory in British Guiana to Venezuela, underpinning a wave of military interventionism. Spurred on by the Monroe Doctrine and Roosevelt's foreign policy, the 'Banana Wars' of 1898-1934 saw US occupations of Cuba, Haiti, Nicaragua, and the Dominican Republic, and interference in the affairs of many more, including Mexico, Venezuela and Panama. The wars ended only as a result of economic depression and incensed Latin American nationalism.

FDR began a new era in America's Latin American policy with the 'Good Neighbour Policy' in 1934, operating under the pretense of non-intervention, but instead on reciprocal trade agreements and cultivating a sphere of influence. It also meant that the US sought to maintain cordial relations with rather ruthless dictators like Batista and Trujillo. This was further buttressed in 1948 with the founding of the Organisation of American States (OAS), which called for respecting the principle of non-intervention.

Though this began to be questioned in Eisenhower's administration with the fear of Communism on the US doorstep, the US was committed not to intervene in Latin America, knowing it couldn't count on OAS support and risked trade losses. Instead the US opted for covert operations involving the newly founded CIA. Perhaps the Agency's most notable success in this regard is its role in the Guatemalan coup d'etat of 1954 (if only at the behest of the United Fruit Company), overthrowing the left leaning presidency of Jacobo Arbenz by supporting the army of authoritarian Carlos Castillo Armas.

It is likely then, that their success in Guatemala and elsewhere led Kennedy to believe that direct US intervention was not necessary in Cuba, since US backed counter-revolutionaries would be more than capable. If US assistance could remain (relatively) covert, it would also curtail any of possibility of anti-American sentiment in Cuba and allow for a much easier transition of power. American intervention in Cuba would also have played badly at home - only around 3% of Americans supported military action against Castro. The costs involved in a US invasion and occupation, in terms of economic costs, casulaties and damage to international relations would also be avoided, and the US would retain its support from the OAS and domestically.

Sources used:

Rabe, Stephen G. (2006). 'The Johnson Doctrine' in Presidential Studies Quarterly. 48-58.

Fisk, Daniel W. (1999). 'Cuba and American Public Opinion' in Association for the Study of the Cuban Economy. 303-321.

Anderson, Tim. (2005). 'Contesting Transition: The US Plan for a "Free Cuba" in Latin American Perspectives. 28-46.