Bilateral relations between the various countries of Latin America and the United States of America have been multifaceted and complex, at times defined by strong regional cooperation and at others filled with economic and political tension and rivalry. Although relations between the U.S. government and most of Latin America were limited prior to the late 1800s, for most of the past century, the United States has unofficially regarded parts of Latin America as within its sphere of influence, and for much of the Cold War (1947–1991), vied with the Soviet Union.

The political context evolved again in the 2000s, with the election in several South American countries of socialist governments. This "pink tide" thus saw the successive elections of Hugo Chávez in Venezuela (1998), Lula in Brazil (2002), Néstor Kirchner in Argentina (2003), Tabaré Vázquez in Uruguay (2004), Evo Morales in Bolivia (2005), Michelle Bachelet in Chile (2006), Daniel Ortega in Nicaragua (2006), Rafael Correa in Ecuador (2006), Fernando Lugo in Paraguay (2008), José Mujica in Uruguay (2009), Ollanta Humala in Peru (2011), Luis Guillermo Solís in Costa Rica (2014), Salvador Sánchez Cerén in El Salvador (2014), and Andrés Manuel López Obrador in Mexico (2018). Although these leaders vary in their policies and attitude towards both Washington, D.C. and neoliberalism, while the states they govern also have different agendas and long-term historic tendencies, which can lead to rivalry and open contempt between themselves, they seem to have agreed on refusing the ALCA and on following a regional integration without the United States' overseeing the process. In particular, Chávez and Morales seem more disposed to ally together, while Kirchner and Lula, who has been criticized by the left-wing in Brazil, including by the Movimento dos Sem Terra (MST) landless peasants movement (who, however, did call to vote for him on his second term), are seen as more centered. The state of Bolivia also has seen some friction with Brazil, as well as Chile. Nouriel Roubini, professor of economics at New York University, said in a May 2006 interview: "On one side, you have a number of administrations that are committed to moderate economic reform. On the other, you've had something of a backlash against the Washington Consensus [a set of liberal economic policies that Washington-based institutions urged Latin American countries to follow, including privatization, trade liberalization and fiscal discipline] and some emergence of populist leaders." In the same way, although a leader such as Chávez verbally attacked the George W. Bush administration as much as the latter attacked him, and claimed to be following a democratic socialist Bolivarian Revolution, the geo-political context has changed a lot since the 1970s. Larry Birns, director of the Council on Hemispheric Affairs, thus stated: for influence in the Western Hemisphere.

Today, the ties between the United States and most of Latin America are generally cordial, but there remain areas of tension between the two sides. Latin America is the largest foreign supplier of oil to the United States and its fastest-growing trading partner, as well as the largest source of illegal drugs and immigration, both documented and otherwise, all of which underline the continually evolving relationship between the region and country.

Overview

Early history Until the end of the 19th century, the US only had a especially close relationship primarily with nearby Mexico and Cuba (apart from Central America, Mexico and the Spanish colony of Cuba), which was largely economically tied to Britain. The United States had no involvement in the process by which Spanish colonies broke away and became independent around 1820. In cooperation with, and help from Britain, the United States issued the Monroe Doctrine in 1823, warning against the establishment of any additional European colonies in Latin America.

Texas, which had been settled by colonies of Americans, fought a successful war for independence from Mexico in 1836. Mexico refused to recognize the independence and warned that annexation to the United States meant war. Annexation came in 1845 and the Mexican–American War began in 1846. The American military was easily triumphant. The result was the Mexican Cession of Santa Fe de Nuevo México and Alta California. About 60,000 Mexicans remained in the territories and became US citizens. France took advantage of the American Civil War (1861–1865) to take over Mexico during the Second French Intervention. Due to defeats in Europe, France pulled out troops, leaving the Imperialists and Maximilian I of Mexico to face defeat from the Benito Juarez-led Republicans (backed by the US).

Rise in American influence The Anglo-Venezuelan boundary dispute in 1895 asserted for the first time a more outward-looking American foreign policy, particularly in the Americas, marking the United States as a world power. This was the earliest example of modern interventionism under the Monroe Doctrine. By the late nineteenth century the rapid economic growth of the United States increasingly troubled Latin America. A Pan-American Union was created under American aegis, but it had little impact as did its successor the Organization of American States.

As unrest in Cuba escalated in the 1890s, the United States demanded reforms that Spain was unable to accomplish. The result was the Spanish–American War of 1898, in which United States acquired Puerto Rico and set up a protectorate over Cuba under the Platt Amendment rule passed as part of the 1901 Army Appropriations Bill. The building of the Panama Canal absorbed American attention from 1903. The US facilitated a revolt that made Panama independent from Colombia and set up the Panama Canal Zone as an American owned and operated district that was finally returned to Panama in 1979. The Canal opened in 1914 and proved a major factor in world trade. The United States paid special attention to protection of the military approaches to the Panama Canal, including threats by Germany. Repeatedly it seized temporary control of the finances of several countries, especially Haiti and Nicaragua.

The Mexican Revolution started in 1910; it alarmed American business interests that had invested in Mexican mines and railways. The United States involvement in the Mexican Revolution, include, among other violations of sovereignty, the ambassadorial backing of a coup and assassination of President Francisco I. Madero and the military occupation of Veracruz. Large numbers of Mexicans fled the war-torn revolution into the southwestern United States. Meanwhile, the United States increasingly replaced Britain as the major trade partner and financier throughout Latin America. The US adopted a "Good Neighbor Policy" in the 1930s, which meant friendly trade relations would continue regardless of political conditions or dictatorships. This policy responded to longstanding Latin American diplomatic pressure for a regional declaration of nonintervention, as well as the increasing resistance and cost of US occupations in Central America and the Caribbean. One effect of the two world wars was a reduction in European presence in Latin America and an increasing solidification of the US position. "The proclamation of the Monroe Doctrine that the hemisphere was closed to European powers, which was presumptuous in 1823, had become effective by the eve of the World War I, at least in terms of military alliances," Friedman and Long note. United States signed up the major countries as allies against Germany and Japan in World War II. However, some countries like Argentina, Chile, Ecuador, Paraguay, Uruguay and Venezuela only declared war on Axis powers in 1945 (though most had broken relations previously).

Cold War The era of the Good Neighbor Policy ended with the ramp-up of the Cold War in 1945, as the United States felt there was a greater need to protect the western hemisphere from Soviet Union influence and a potential rise of communism. These changes conflicted with the Good Neighbor Policy's fundamental principle of non-intervention and led to a new wave of US involvement in Latin American affairs. "In the 1950s, the United States shifted from an earlier tradition of direct military intervention to covert and proxy interventions in the cases:

Guatemala (1954), Cuba (1961), Guyana (1961–1964), Chile (1970–1973), and Nicaragua (1981–1990), as well as outright military invasions of the Dominican Republic (1965), Grenada (1983), and Panama (1989)."

Furthermore, during the 1970s, the Nixon Administration would exercise immense economic and political pressure. Henry Kissinger, Nixon's Secretary of State, spearheaded the administration's relations in the region and crafted the very circumstances necessary for pro-American leaders to take over. The first decade of the Cold War saw relative high degrees of consensus between US and Latin American elites, centered on anti-communism, though with divergences over the direction of economic policy. Later decades of the Cold War saw higher levels of violence in conflicts with overlapping local, US-Latin American, and global Cold War dimensions, referred to by historian Tanya Harmer as the "inter-American Cold War." The turn of Castro's revolution in Cuba after 1959 toward Soviet communism alienated Cuba from the United States, though reactions to the revolution varied considerably across Latin America. An attempted invasion failed and at the peak of the Cold War in 1962, the Cuban Missile Crisis threatened major war as the Soviet Union installed nuclear weapons in Cuba to defend it from an American invasion. The crisis also shook the domestic politics of Latin American countries, where governments initially exhibited little sympathy for Cuba. There was no invasion, but the United States imposed an economic boycott on Cuba that remains in effect, as well as a breaking off of diplomatic relations, that lasted until 2015. The US also saw the rise of left-wing governments in central America as a threat and, in some cases, overthrew democratically elected governments perceived at the time as becoming left-wing or unfriendly to U.S. interests. Examples include the 1954 Guatemalan coup d'état, the 1964 Brazilian coup d'état, the 1973 Chilean coup d'état and the support of the Contra rebels in Nicaragua. After 1960, Latin America increasingly supplied illegal drugs, especially marijuana and cocaine to the rich American market. One consequence was the growth of violent drug gangs in Mexico and other parts of Central America attempting to control the drug supply. The United States would often back anybody they say as an ally in the fight against communism, including dictatorships such as the Somoza regime in Nicaragua. The Somoza regime would be overthrown in 1979 by the Sandinista Nation Liberation Front, which was a left-wing group that was backed by Cuba and other socialist countries. This along with dozens of other battles between political groups in Latin America only added more tension and division to Latin America's Cold War. As the United States struggled through Vietnam and through the oil shocks, Latin American countries took notice. Many countries, like Venezuela, saw these moments as a chance to space some of the firm grasp the US had put on Latin America and begin to get more from the table. Countries were able to broker new deals that allowed them to grow massively economically, Venezuela became a major supplier of the world's oil, but most importantly, Latin American countries no longer felt like they had to pick between the US and the USSR, but rather be sovereign.