United States intervention in Chilean politics started during the War of Chilean Independence (1812–1826). The influence of United States in both the economic and the political arenas of Chile has since gradually increased over the last two centuries and continues to be significant.

Chilean independence The arrival of Joel Roberts Poinsett, in 1811, marked the beginning of U.S. involvement in Chilean politics. He had been sent by President James Madison in 1809 as a special agent to the South American Spanish colonies (a position he filled from 1810 to 1814) to investigate the prospects of the revolutionaries, in their struggle for independence from Spain.

War scare of 1891 During the 1891 Chilean Civil War, the U.S. backed President José Manuel Balmaceda, as a way to increase their influence in Chile, while Britain backed the successful Congressional forces.

Itata incident

The Itata incident concerned an attempted shipment of 5,000 rifles in 1891 by the ship Itata of arms purchased in California from Remington. The U.S. Navy was supported with a fleet of a multi-national ships, some from the Royal Navy and Imperial German Kaiserliche Marine. This fleet went to the port of Iquique and convinced the port authorities to hand over the weapons.

Baltimore crisis

The U.S. Government sent a warship to Chile to protect American interests. The crew of the Baltimore took shore leave at Valparaíso. During the US sailors' shore leave on 16 October 1891, a mob of enraged Chileans angry about the Itata's capture, attacked them. Two American sailors were killed, 17 were wounded and 36 others were jailed. That Valparaíso riot prompted saber rattling from enraged US officials. A war between the U.S. and Chile was remotely possible. Chile's foreign minister escalated the tension, but U.S. Secretary of State James G. Blaine managed to de-escalate rising tensions. The crisis ended when the Chilean government bowed, and while maintaining that the seamen were to blame for the riot, paid an indemnity of $75,000 to the victims' families.Joyce S. Goldberg, "Consent to Ascent The Baltimore Affair and the US Rise to World Power Status." Americas 41.1 (1984): 21-35.

Early 20th century

United States involvement in Chilean affairs intensified in the early decades of the 20th century. After World War I, the United States replaced Britain as the leading superpower controlling most of Chile's resources and economic activity. This shift hindered Chile from profiting as a result of the war and gaining financial independence. The dependence on the United States formally began in the early years of the 1920s as two major US companies, Anaconda and Kennecott, took control of the valuable resources. Up until the 1970s, "both industries controlled between 7% to 20% of the country's gross domestic product".Theodore H. Moran, Multinational corporation and the politics of dependence: copper in Chile (Princeton, New Jersey: Princeton University Press, 1974), 6.

The conclusion of World War II resulted in a similar situation, as Chile could not exploit the "excess of copper they produced, as almost all the copper was marketed through subsidiaries of United States copper firms established in Chile for whom the allied government fixed a ceiling price upon copper products during the course of the war."Loveman, Brian. Chile: The legacy of Hispanic Capitalism. New York: Oxford University Press, 2001.

As the working class demanded an improvement in their standard of living, higher wages and improved working conditions, the notion that a left-wing government could be the solution for the people began to take form.

1950s and 1960s

During the 1950s and 1960s, the United States put forward a variety of programs and strategies, ranging from funding political campaigns to funding propaganda, aimed at impeding the presidential aspirations of left-wing candidate Salvador Allende, who served as President of the Senate (1966–1969) before running a final time to become the 28th president of Chile, which lasted until his death in 1973. Throughout these two decades, left-wing parties in Chile failed to gain power, in part due to the fact that the United States was impeding these parties through various means. In the 1958 presidential election, Jorge Alessandri – a nominal independent with support from the Liberal and Conservative parties – defeated Allende by nearly 33,500 votes to claim the presidency.Barbara Stallings, Class conflict and Economic development in Chile, 1958–1973. Stanford, California: Stanford University Press, 1978, 33. His laissez-faire policies, endorsed by the United States, were regarded as the solution to the country's inflation problems. Under recommendations from the United States, Alessandri steadily reduced tariffs starting in 1959, a policy that caused the Chilean market to be overwhelmed by American product. These governmental policies angered the working class of Chile, who demanded higher wages, and the repercussions of this massive discontent were felt in the 1961 congressional elections. The president suffered terrible blows, sending the message that laissez-faire policies were not desired. As the "grand total of $130 million from the U.S. banking industry, the U.S. Treasury Department, the IMF and the ICA"Faundez Julio, Marxism, and democracy in Chile: From 1932 to the fall of Allende. London United Kingdom: Yale University Press, 1988. accepted by Alessandri illustrates, laissez-faire policies may have induced the opposite of the intended effect – making Chile more dependent on the United States, not less.

Presidential candidate Salvador Allende was a top contender in the 1964 election. The U.S., through the Central Intelligence Agency (CIA), covertly spent three million dollars campaigning against him,CIA Reveals Covert Acts In Chile , CBS News, 19 September 2000. Accessed online 19 January 2007. before and after the election, mostly through radio and print advertising. The Americans viewed electing Christian Democratic contender Eduardo Frei Montalva as vital, fearing that Alessandri's failures would lead the people to support Allende. Allende was feared by the Americans because of his warm relations with Cuba and his open criticism of the Bay of Pigs Invasion. Furthermore, clandestine aid to Frei was put forward through John F. Kennedy's Latin American Alliance for Progress, which promised "$20 billion in public and private assistance in the country for the next decade."Stephen G. Rabe, The most dangerous Area in the world: John F. Kennedy Confronts Communist Revolution in Latin America (Chapel Hill: The University of North Carolina Press, 1999), 2.

The 1970 election According to a U.S. Senate select committee, publishing a Church Commission Report in 1975 to describe international abuses committed by the CIA, NSA, and FBI, covert United States involvement in Chile in the decade between 1963 and 1973 was "extensive and continuous". The CIA spent $8 million in the three years between 1970 and the military coup of September 1973, with over $3 million allocated toward Chilean intervention in 1972 alone. Covert American activity was present in almost every major election in Chile in the decade between 1963 and 1973, but its tangible effect on electoral outcomes is not altogether clear. Chile, more than any of its South American neighbors, had a long-standing democratic tradition dating back to the early 1930s, and it has been difficult to gauge how successful CIA tactics were in swaying voters.

A declassified file from August 19, 1970, reveals the minutes of high-level officials in the CIA known as the "Special Review Group." It was chaired by Henry Kissinger and was sanctioned by President Nixon. This was one of several documents released as part of the Foreign Relations of the United States (FRUS) series dedicated toward US-Chilean interventionalism – collectively known as Foreign Relations of the United States, 1969–1976, Volume XXI, Chile, 1969–1973 and Foreign Relations, 1969–1976, Volume E–16, Documents on Chile, 1969–1973 – that revealed a detailed account of correspondences between each of these officials, telegrams from the Chilean embassy, memorandums, and "special reports" concerning the state of affairs in Chile. For instance, a National Intelligence Estimate from January 28, 1969, stated the problems and conclusions that senior officials in Washington identified over the proliferating crisis in Chile. The document indicates that the 1970 election stood above all other issues as of critical importance, with Chile's political and economic stability depending heavily on that particular election's outcome; the document notes the possibility of out of control economic stagnation and inflation in Chile as concerns. The conclusions of the document suggest that factionalism needed to be addressed, and expounded on United States interests in copper extraction companies operating in Chile. The election represented the potential for important economic relations to collapse or continue. The document further focuses on potential ramifications if the election outcome were to not align with US interests.

At a 8 September 1970 meeting of the 40 Committee, the chairman of the committee asked for an analysis of where the U.S. and CIA stood in terms of taking action to prevent Allende from becoming President of Chile. William Broe, a high-ranking CIA officer, said Eduardo Frei Montalva, the 29th president of Chile, was essential to the situation, regardless of the type of involvement — military or congressional. The 40 Committee asked that the CIA collect information and create more intelligence reports to see what could be further done in Chile. The committee decided it was unlikely they were going to be able to influence the 24 October congressional election to go against Allende. Richard Helms was also concerned about Allende supporters in the Chilean military, as it seemed they would support Allende in the event of a coup. As a result of all this information, the committee requested a full analysis of two things: (1.) a cost-versus-benefit analysis of organizing a military (Chilean) coup; (2.) a cost-versus-benefit analysis of organizing future oppositions to Allende to topple his influence. This presented two options for Henry Kissinger: political maneuvering or outright force.

Four days after the 8 September 1970 meeting of the 40 Committee, a cable between Helms and Henry Kissinger discussed the lack of morale that the U.S. embassy had in Chile according to the American ambassador to Chile, Edward Korry. Kissinger stated in response that he would call another 40 Committee meeting for the following Monday. Kissinger further said "we will not let Chile go down the drain."

Allende presidency

Salvador Allende ran again in the 1970 presidential election, winning a narrow victory plurality vote (near 37%). U.S. President Richard Nixon feared that Chile could become "another Cuba" and cut off most foreign aid to Chile. The U.S. Government believed that Allende would become closer to socialist countries such as Cuba and the Soviet Union. They feared that Allende would push Chile into socialism, resulting in the loss of all the U.S. investments made in Chile.