Balaguer emerged victorious in the elections, after building his campaign on promises of reconciliation. On September 21, 1966, the last OAS peacekeepers withdrew from the island, ending the foreign intervention in the conflict. Through the Office of Public Safety, an organization dependent of the USAID and close to the CIA, the US assisted Latin American security forces, training them in interrogation methods, riot control, and sending them materiel. Dan Mitrione in Uruguay became infamous for his systematic use of torture. Following the 1959 Cuban Revolution and the local implementation in several countries of Che Guevara's foco theory, the US waged a war in South America against what it called "Communist subversives", leading to support of coups against democratically elected presidents such as the backing of the Chilean right wing, which would culminate with Augusto Pinochet's 1973 Chilean coup against democratically-elected Salvador Allende. By 1976, all of South America was covered by similar military dictatorships, called "juntas". In Paraguay, Alfredo Stroessner had been in power since 1954; in Brazil, left-wing President João Goulart was overthrown by a military coup in 1964 with the assistance of the US in what was known as Operation Brother Sam; in Bolivia, General Hugo Banzer overthrew leftist General Juan José Torres in 1971; in Uruguay, considered the "Switzerland" of South America, Juan María Bordaberry seized power in the 27 June 1973 coup. In Peru, leftist General Velasco Alvarado in power since 1968, planned to use the recently empowered Peruvian military to overwhelm Chilean armed forces in a planned invasion of Pinochetist Chile. A "Dirty War" was waged all over the subcontinent, culminating with Operation Condor, an agreement between security services of the Southern Cone and other South American countries to repress and assassinate political opponents, which was backed by the US government. The armed forces also took power in Argentina in 1976, and then supported the 1980 "Cocaine Coup" of Luis García Meza Tejada in Bolivia, before training the "Contras" in Nicaragua, where the Sandinista National Liberation Front, headed by Daniel Ortega, had taken power in 1979, as well as militaries in Guatemala and in El Salvador. In the frame of Operation Charly, supported by the US, the Argentine military exported state terror tactics to Central America, where the "dirty war" was waged until well into the 1990s, making hundreds of thousands "disappeared".