Now I imagine it would take sometime to actually verify all of this data, but I will provide some of it and the link.
1973 U.S.-supported military coup kills Allende and brings Augusto Pinochet Ugarte to power. Pinochet imprisons well over a hundred thousand Chileans (torture and rape are the usual methods of interrogation), terminates civil liberties, abolishes unions, extends the work week to 48 hours, and reverses Allende's land reforms.
1973 Military takes power in Uruguay, supported by U.S. The subsequent repression reportedly features the world's highest percentage of the population imprisoned for political reasons.
1974 Office of Public Safety is abolished when it is revealed that police are being taught torture techniques.
1976 Election of Jimmy Carter leads to a new emphasis on human rights in Central America. Carter cuts off aid to the Guatemalan military (or tries to; some slips through) and reduces aid to El Salvador.
1979 Ratification of the Panama Canal treaty which is to return the Canal to Panama by 1999.
"Once again, Uncle Sam put his tail between his legs and crept away rather than face trouble." --Ronald Reagan
1980 A right-wing junta takes over in El Salvador. U.S. begins massively supporting El Salvador, assisting the military in its fight against FMLN guerrillas. Death squads proliferate; Archbishop Romero is assassinated by right-wing terrorists; 35,000 civilians are killed in 1978-81. The rape and murder of four U.S. churchwomen results in the suspension of U.S. military aid for one month.
The U.S. demands that the junta undertake land reform. Within 3 years, however, the reform program is halted by the oligarchy.
"The Soviet Union underlies all the unrest that is going on." --Ronald Reagan
1980 U.S., seeking a stable base for its actions in El Salvador and Nicaragua, tells the Honduran military to clean up its act and hold elections. The U.S. starts pouring in $100 million of aid a year and basing the contras on Honduran territory.
Death squads are also active in Honduras, and the contras tend to act as a state within a state.
1981 The CIA steps in to organize the contras in Nicaragua, who started the previous year as a group of 60 ex-National Guardsmen; by 1985 there are about 12,000 of them. 46 of the 48 top military leaders are ex-Guardsmen. The U.S. also sets up an economic embargo of Nicaragua and pressures the IMF and the World Bank to limit or halt loans to Nicaragua.
1981 Gen. Torrijos of Panama is killed in a plane crash. There is a suspicion of CIA involvement, due to Torrijos' nationalism and friendly relations with Cuba.
1982 A coup brings Gen. Efraín Ríos Montt to power in Guatemala, and gives the Reagan administration the opportunity to increase military aid. Ríos Montt's evangelical beliefs do not prevent him from accelerating the counterinsurgency campaign.
1983 Another coup in Guatemala replaces Ríos Montt. The new President, Oscar Mejía Víctores, was trained by the U.S. and seems to have cleared his coup beforehand with U.S. authorities.
1983 U.S. troops take over tiny Granada. Rather oddly, it intervenes shortly after a coup has overthrown the previous, socialist leader. One of the justifications for the action is the building of a new airport with Cuban help, which Granada claimed was for tourism and Reagan argued was for Soviet use. Later the U.S. announces plans to finish the airport... to develop tourism.
1983 Boland Amendment prohibits CIA and Defense Dept. from spending money to overthrow the government of Nicaragua-- a law the Reagan administration cheerfully violates.
1984 CIA mines three Nicaraguan harbors. Nicaragua takes this action to the World Court, which brings an $18 billion judgment against the U.S. The U.S. refuses to recognize the Court's jurisdiction in the case.
1984 U.S. spends $10 million to orchestrate elections in El Salvador-- something of a farce, since left-wing parties are under heavy repression, and the military has already declared that it will not answer to the elected president.
1989 U.S. invades Panama to dislodge CIA boy gone wrong Manuel Noriega, an event which marks the evolution of the U.S.'s favorite excuse from Communism to drugs.
1996 The U.S. battles global Communism by extending most-favored-nation trading status for China, and tightening the trade embargo on Castro's Cuba.
Here is the link, now I know the U.S practically supported a scorched earth policy in South America for a long time, but I do not know to exactly what extent.
link