for illegitimate children. However, Bosch faced powerful enemies. He moved to break up latifundia, drawing the ire of landowners. The Church thought Bosch was trying to oversecularize the . Industrialists did not like the new Constitution's guarantees for the working class. The military, who previously enjoyed free rein, felt Bosch put them on too short a leash. Coup d'état On 25 September 1963, after only seven months in office, Bosch was overthrown in a coup led by Colonel Elías Wessin and replaced by a three-man military junta. Bosch went back to exile in Puerto Rico. Less than two years later, growing dissatisfaction generated another military rebellion on 24 April 1965, that demanded Bosch's restoration. The insurgents, commanded by Colonel Francisco Caamaño, removed the junta from power on April 28. The United States dispatched 42,000 troops to the island in Operation Power Pack during the ensuing civil war in support of the anti-Bosch forces. An interim government was formed, and elections were fixed for 1 July 1966. Bosch returned to the country and ran as his party's presidential candidate. However, he ran a somewhat muted campaign, fearing for his safety and believing he would be thrown out of office by the military again if he won. He was soundly defeated by Joaquín Balaguer, who garnered 57% of the vote. The last US battalion left in September 1966. During the last half of the 1960s, Bosch remained a very prolific writer of essays, both political and historical. He published some of his most important works during this time: "Dominican Social Composition", "Brief History of the Oligarchy in Santo Domingo", "From Christopher Columbus to Fidel Castro", and numerous articles of different sorts. By 1970, Bosch had the intention of reorganizing the PRD and turning its members into active, studious militants of the historical and social reality of the country. His project was not accepted by most of the PRD, most of whose members were turning in a more mainstream social democratic direction. Also, given the military repression, and lack of political equality between the PRD and the official Reformist Party, Bosch abstained from the 1970 elections. Bosch became studious of Marxist ideology. He will describe himself as a "Marxist- non Leninist". The differences and contradictions between Bosch and an important sector of the PRD on ideology, as well as the corruption that had started to grow within the party, made him leave the