While the military occupation improved the island republic's infrastructure to some degree, nationalist opposition to U.S. rule was especially focused on the U.S.-established National Guard, which oftentimes acted with considerable brutality. When the United States withdrew its forces from the country, it left power in the hands of the National Guard, led by Rafael Trujillo. Trujillo ruled the Dominican Republic for more than three decades, from 1930 until his assassination in May 1961.
During World War II the Dominican Republic was one of the first Latin American countries to declare war on the Axis powers, and Trujillo paid brief lip service to democratic principles. After the war, however, beginning in 1947 he moved to reverse his toleration of opposition parties and for the next twenty years relied on his powerful allies in Washington to neutralize international opposition to his regime.
Trujillo ruled with considerable savagery, using the National Guard and his feared secret police force to suppress and eliminate any political dissent. Meanwhile, he treated the Dominican Republic as his personal fiefdom. Until the late 1950s, Trujillo enjoyed the uncritical support of the United States. He also quickly learned how to exploit Cold War fears of communism in the Caribbean to secure favors from Washington.
The removal of Trujillo in May 1961 was partly assisted by the growth of inter-American and U.S. opposition to his brutal rule and a decision by the John F. Kennedy administration to reduce American support and impose economic sanctions. The period between Trujillo's assassination and the 1965 U.S. military intervention was marked by a complicated history of attempts to create a stable political climate in which Trujillo's cronies and relatives tried, unsuccessfully, to continue the dictator's rule.
In national elections in 1962, the first democratic elections in nearly four decades, a nationalist-reformist coalition, the Dominican Revolutionary Party (PRD), came to power with the support of middle-class sectors and some populist movements. The new government was headed by the Dominican novelist Juan Bosch. After an initial honeymoon period in which the Kennedy administration responded warmly to the new government, relations with Washington began to deteriorate, especially when Bosch made clear his intentions to recognize the Cuban government of Fidel Castro. Bosch's economic reforms, which included modest land reform and the nationalization of several major enterprises, further aroused anti-communist fear within the Dominican Republic and in the United States.
With signs of U.S. approval, in September 1963 elements of the nation's armed forces led by archconservative General Elias Wessin y Wessin overthrew Bosch, who went into exile in Puerto Rico. The coup installed a military triumvirate headed by businessman Donald Reid Cabral.
The leaders of the new regime abolished the constitution, but nearly two years of corruption and brutal internal repression produced a popular uprising on 24 April 1965, which restored Bosch and his Constitutionalist movement to power. For four days the Constitutionalists and their military and civilian supporters, led by Colonel Francisco Caamaño, fought to prevent a counterattack led by Wessin y Wessin.
The fighting in Santo Domingo soon took on the characteristics of a popular insurrection and began to spread to other regions of the country. Despite their use of tank assaults and aerial bombing, the Wessin-led forces were on the verge of defeat. The impending collapse of the Wessin forces and faulty intelligence supplied by U.S. Ambassador William Tapley, who reported to the U.S. State Department that the lives of American citizens were imperiled by communist-led hordes, set the scene for a full-scale U.S. intervention.
On 28 April 1965, a clearly panicked President Lyndon B. Johnson ordered 20,000 U.S. troops into the Dominican Republic. The Americans' official rationale was that the action was needed to prevent a communist takeover of the country and the emergence of a "second Cuba." Evidence of communist influence within the insurrection was, however, very thin. The Communist Party's small number of militants and the members of the Castroite June 14 Movement certainly played a role in the Constitutionalist resistance, but the popular insurrection was overwhelmingly made up of the urban poor of Santo Domingo. The American intervention in practice seemed designed to prevent a return to Constitutional government by Bosch and to block radical social and economic change in the island republic.
U.S. intervention forces were soon aided by an Organization of American States (OAS) intervention peace force. The OAS force was the result of vigorous U.S. lobbying and was in violation of inter-American prohibitions on foreign military intervention in the affairs of the region. American and OAS forces took a month to defeat the Constitutionalist insurrection and impose an interim administration before new elections were convened. In the elections of June 1966, a large majority of voters elected Joaquín Balaguer, a former Trujillo loyalist, and his Reformist Party. Balaguer remained in power for most of the next twenty-eight years. Systematic police terror, an astronomical increase in political corruption, and the transformation of the Dominican Republic into a secure location for foreign investors were the main legacies of the U.S. intervention.
Gleijeses, Piero. The Dominican Crisis: The 1965 Constitutionalist Revolt and American Intervention. Baltimore: Johns Hopkins University Press, 1978.; Moreno, José. Barrios in Arms: Revolution in Santo Domingo. Pittsburgh, PA: University of Pittsburgh Press, 1970.