Mexico and the United States have a strained history, with the American invasion in the 1840s and the subsequent American occupation and annexation of more than 50% of former Mexican territory, including Texas, Arizona, California, Nevada, Utah, parts of Colorado, parts of Oklahoma, parts of Kansas and New Mexico. Pressure from the American government was one of the factors that helped force the French invaders out in the 1860s. During the Mexican Revolution of the 1910s, the coup against mexican president Francisco I. Madero was heavily supported by the American government through the pact of the embassy. Other tensions resulted in the Cold War through the so-called Mexican Dirty War. The two nations share a maritime and land border. Several treaties have been concluded between the two nations bilaterally, such as the Gadsden Purchase, and multilaterally, such as the 2019 United States–Mexico–Canada Agreement, replacing the 1994 NAFTA. Both are members of various international organizations, including the Organization of American States and the United Nations. According to Adolfo Aguilar Zínser, mexican diplomat and intellectual, the political and intellectual class of the United States sees Mexico as "a country whose position is that of a backyard".

Since the late nineteenth century, during the regime of President Porfirio Díaz (1876–1911), the two countries have had close diplomatic and economic ties. During Díaz's long presidency, U.S. businessmen acquired agricultural and mining interests in the country. The U.S. played an important role in the course of the Mexican Revolution (1910–20) with direct actions of the U.S. influencing the outcome. The long border between the two countries means that peace and security in that region are important to the U.S.'s national security and international trade. The U.S. and Mexico are each other’s largest trading partners as of 2023. In 2010, Mexico's exports totaled US$309.6  billion, and almost three quarters of those purchases were made by the United States. They are also closely connected demographically, with over one million U.S. citizens living in Mexico and Mexico being the largest source of immigrants to the United States, with about 8-10 million Mexican immigrants in the US.

While condemning the terrorist attacks of 9/11 and providing considerable relief aid to the U.S. after Hurricane Katrina, the Mexican government, pursuing neutrality in international affairs, opted not to actively join the war on terror and the Iraq War, instead being the first nation in history to formally and voluntarily leave the Inter-American Treaty of Reciprocal Assistance in 2002.

Country comparison Mexico United States of America Coat of Arms Flag Population 131,946,900 Area Population Density Capital Mexico City Washington, D.C. Largest City Mexico City – 9,209,944 (21,804,515 Metro) New York City – 8,600,710 (19,006,798 Metro) Government Federal presidential constitutional republic Federal presidential constitutional republic First Leader Agustín de Iturbide George Washington Current Leaders Claudia Sheinbaum Donald Trump Official languages Spanish English (de facto, none at federal level) GDP (nominal) US$1.783 trillion US$30.615 trillion

History

The United States of America shares a unique and often complex relationship with the United Mexican States. With shared history stemming back to the Texas Revolution (1835–1836) and the Mexican–American War (1846–1848), several treaties have been concluded between the two nations, most notably the Gadsden Purchase, and multilaterally with Canada, the North American Free Trade Agreement (NAFTA). Mexico and the United States are members of various international organizations, such as the Organization of American States and the United Nations. Boundary disputes and allocation of boundary waters have been administered since 1889 by the International Boundary and Water Commission, which also maintains international dams and wastewater sanitation facilities. Once viewed as a model of international cooperation, in recent decades the IBWC has been heavily criticized as an institutional anachronism, bypassed by modern social, environmental, and political issues.Robert J. McCarthy, Executive Authority, Adaptive Treaty Interpretation, and the International Boundary and Water Commission, U.S.-Mexico, 14-2 U. Denv. Water L. Rev. 197(Spring 2011) (also available for free download at https://ssrn.com/abstract=1839903). Illegal immigration, arms sales, and drug smuggling continue to be contentious issues in 21st-century U.S.-Mexico relations.

Since 1945

The alliance between Mexico and the U.S. during World War II brought the two countries into a far more harmonious relationship with one another. Mexican President Manuel Avila Camacho met in person with both Franklin D. Roosevelt and Harry S. Truman, helping to cement ties with the U.S. Avila Camacho was not a leader in the Mexican Revolution himself, and held opinions that were pro-business and pro-religious that were more congenial to the U.S. while he maintained revolutionary rhetoric. During Avila Camacho's visit with Truman near the centenary of the Mexican–American War, Truman returned some of the Mexican banners captured by the United States in the conflict and praised the military cadets who died defending Mexico City during the invasion.Jürgen Buchanau, "Foreign Policy, 1946–1996," in Encyclopedia of Mexico, vol. 1, p. 511. Chicago: Fitzroy Dearborn 1997.

For bilateral relations between the U.S. and Mexico, the end of World War II meant decreased U.S. demand for Mexican labor via the guest-worker Bracero Program and for Mexican raw materials to fuel a major war. For Mexican laborers and Mexican exporters, there were fewer economic opportunities. However, while at the same time, the government's coffers were full and aided post-war industrialization.Buchanau, "Foreign Policy, 1946–1996," pp. 510–11. Chicago: Fitzroy Dearborn 1997. In 1946, the dominant political party changed its name to the Institutional Revolutionary Party, and while maintaining revolutionary rhetoric, it in fact embarked on industrialization that straddled the line between nationalist and pro-business policies. Mexico supported U.S. policies in the Cold War and did not challenge U.S. intervention in Guatemala that ousted leftist president Jacobo Arbenz.Buchenau, "Foreign Policy, 1946–1996," pp. 511–12.

Boundary issues and the border region

Under Mexican president Adolfo López Mateos, the U.S. and Mexico concluded a treaty on January 14, 1964, to resolve the Chamizal dispute over the boundary between the two countries, with the U.S. ceding the disputed territory.Buchenau, "Foreign Policy, 1946–1996," p. 512. The Boundary Treaty of 1970 resolved further issues between the two countries. Since then, jurisdictional issues regarding water rights in the Rio Grande Valley have continued to cause tension between farmers on both sides of the border, according to Mexican political scientist Armand Peschard-Sverdrup.

North American Free Trade Agreement (since 1994)

Mexico, the United States, and Canada signed the North American Free Trade Agreement (NAFTA) in 1994 to eliminate barriers to trade and investment.

After securing the NAFTA treaty that integrated the Mexican and American economies, President Bill Clinton faced yet another foreign crisis in early 1995. The Mexican peso began to fall sharply and threatened the collapse of the Mexican economy. Clinton feared that a collapse would hurt the United States because of their close economic ties. He proposed a plan to address the financial crisis in Mexico, but many in Congress, fearing that constituents would not favor aid money to Mexico, rejected the plan. In response, Clinton used executive authority to create a $20 billion loan package for Mexico to restore international confidence in the Mexican economy. The loan went through, and Mexico completed its loan payments to the United States in January 1997, three years ahead of schedule. However, issues such as drug smuggling and immigration continued to strain relations.Russell Dean Covey, "Adventures in the Zone of Twilight: Separation of Powers and National Economic Security in the Mexican Bailout." Yale Law Journal 105 (1995): 1311-1345. Online

Illegal immigration from Mexico

In 2017, 47% of illegal immigrants in the United States originate from Mexico. The United States has built a barrier on much of its border with Mexico.Michael P. Dino, Evaluator-in-Charge & James R. Russell, Evaluator. December 1994 Border Control: Revised Strategy Is Showing Some Positive Results: Report to the Chairman, Subcommittee on Information, Justice, Transportation and Agriculture, Committee on Government Operations, House of Representatives http://www.druglibrary.org/schaffer/govpubs/gao/gao13.htm In recent years, the majority crossing from Mexico into the United States have been from Central America.

Illegal trade of weapons

The US is the largest source of illicit traffic of weapons traffic to Mexico. Many of the traceable weapons come from American weapons markets and festivals that do not have regulations for the buyers, and there is a geographic coincidence between the supposed American origin of the firearms and the places where these weapons are seized, mainly in the Northern Mexican states. Firearms that make their way to Mexico come from the American civilian market. Grenades are also smuggled from the US to Mexico. In an effort to control the smuggling of firearms, the U.S. government is assisting Mexico with technology, equipment, and training. Project Gunrunner was one such efforts between the U.S. and Mexico to collaborate in tracing Mexican guns which were manufactured in or imported legally to the U.S.

In 2015, Official reports of the U.S. government and the Bureau of Alcohol, Tobacco, Firearms and explosives (ATF) revealed that Mexican cartels improved their firearm power over that last years, and that 70% of their weapons come from the U.S.

ATF gunwalking scandal

The American ATF's Project Gunrunner has as its stated purpose the stoppage of the selling and exportation of guns from the United States into Mexico, to deny Mexican drug cartels the firearms considered "tools of the trade". However, in February 2011, it brought about a scandal when the project was accused of accomplishing the opposite by ATF permitting and facilitating "straw purchase" firearm sales to traffickers, and allowing the guns to "walk" and be transported to Mexico. Several of the guns sold under the Project Gunrunner were recovered from crime scenes in Arizona and at crime scenes throughout Mexico.Michael Krantz, "Walking firearms to gunrunners: ATF's flawed operation in a flawed system." Journal of Criminal Law and Criminology 103 (2013): 585+.

Obama administration

Mexico was not high on the priorities of the Obama Administration, but slow progress was made on security issues.Andrew Selee and Eric L. Olson, "Steady Advances, Slow Results: US-Mexico Security Cooperation After Two Years of the Obama Administration." Woodrow Wilson International Center for Scholars 3 (2011) online.

As of 2013, Mexican students formed the 9th largest group of international students studying in the United States, representing 1.7% of all foreigners pursuing higher education in the U.S.

First Trump administration

The four-year term of President Donald Trump, who had provoked the ire of the Mexican government through threats against companies who invest in Mexico instead of the U.S., and his claims that he would construct a border wall and force Mexico to fund its construction, caused a decline in the relations of the two countries in the late 2010s.