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The Treaty of Guadalupe-Hidalgo in the Trump Era

The Treaty of Guadalupe-Hidalgo in the Trump Era
Alejandro García Magos | March 2017

Does Mexico have something to gain by triggering a territorial dispute with the U.S. over the outcome of the war between them 168 years ago? Some prominent politicians in Mexico think so. But not because they expect to recover an inch of land, but because it can potentially counter the aggressive rhetoric of the Trump administration.

In memoriam Ana Maria Bejarano, Professor of Political Science at the University of Toronto, and author's PhD supervisor.

Shortly after I moved to Canada my new in-laws came to visit from Texas. We had a great time except for a minor snag. One evening the conversation turned to politics and my father-in-law grumbled about how porous the U.S.-Mexico border was. Jokingly, I responded that he should not be surprised, since after all Texas had been part of Mexico at some point. He did not laugh, and the lighthearted mood of the evening turned a bit sour.

I was not trying to be deliberately caustic. My response had a lot to do with the fact that at the time I was enrolled in a nineteenth-century Mexican History course for my master’s degree, and I was a bit hung up on the intricacies of the Mexican-American War (1846-1848) in which Mexico lost half of its territory. The instructor of the course, a well-reputed Canadian historian on Spanish America, liked to provoke the class by claiming that the outcome of the war was neither inevitable nor should it be considered definitive. According to him, had the Mexican forces held their ground on the Battle of Cerro Gordo in the mountains of Veracruz, the invading U.S. Marines would in all likelihood have succumbed to yellow fever.

More contentiously, he also suggested that the Treaty of Guadalupe-Hidalgo, which put an end to the war, had little legal foundation and could be subject to judicial revision at any moment. To make this last point, he referred to three examples of ongoing judicial battles in our continent between modern states over territorial disputes dating back to past centuries: 1) the conflict between Bolivia, Peru, and Chile, which originated in the War of the Pacific (1879-1883); 2) the Belizean-Guatemalan border row, which has flared up every now and then since 1821; and 3) the conflict between Argentina and the U.K. over the Malvinas/Falklands, stretching all the way since 1833. 

But as much as I enjoyed the counterfactuals in Mexican history, I never thought any serious politician in Mexico would ever call for revisiting the Treaty of Guadalupe-Hidalgo. Well, I was wrong. Recently, Cuauhtémoc Cárdenas, the grand old man of the Mexican left, announced he was seeking the annulment of the Treaty. According to Cárdenas and his team of lawyers, there is enough legal grounds for this because “in the first sentence of the Guadalupe-Hidalgo Treaty the U.S. army acknowledges that it invaded our country. Signing a treaty under those conditions makes it not legally binding from the outset.” (1) Specifically, Cárdenas’ plan, as he himself explained, is to bring the case to the International Court of Justice (ICJ) and demand from the U.S. the return of the territory that now constitutes California, New Mexico, Arizona, Nevada, Utah, and some areas of Colorado, Wyoming, Kansas and Oklahoma. If the ICJ rules in favour of Mexico, and given the fact that the territory in question is now heavily populated compared to 1848, Mexico would then seek a monetary compensation from the U.S. for the use of the land over the past 168 years.

Treaty of Hidalgo Guadalupe. Photo: Library of Congress

It is important to underline that this plan is envisaged not by a hot-headed nationalist, but by one of the most senior and respected politicians in Mexico, a key figure in its political history over the past century, and a three-time presidential candidate (in 1988, 1994, and 2000). Even if it sounds far-fetched, the temptation to dismiss his plan altogether must be resisted. What Cárdenas is likely after is to put pressure on the Mexican government to regain the initiative in its relationship with the U.S. After all, he has been a vocal critic of the way president Peña Nieto has handled the Trump phenomenon, accusing him of submission and lacking firmness to defend the interests and dignity of Mexico. In his defense, Peña Nieto argues that, given the erratic nature of the new U.S. president, caution and restraint are necessary in dealing with him. The difference of opinion between these two Mexican leaders also has an electoral dimension: next year there will be presidential elections in Mexico and the electoral season is gearing up.

But beyond internal political skirmishes, is Cárdenas’ plan to revisit the Treaty of Guadalupe-Hidalgo politically advantageous? First, some pros. Mexico would shift away from a defensive position and retake the political initiative, a welcome change after months of being Mr. Trump’s favourite punching bag. It could also potentially counter the victimhood narrative in which Mr. Trump frames the U.S.-Mexico relationship when he states that “Mexico has taken advantage of the U.S. for long enough.” (2) On the con side, in the current anti-immigrant climate in the U.S., any claim calling into question the legitimacy of the U.S. authority over its territories would likely be harshly opposed, both in official channels and outside them. Also, portraying Mexico as the legitimate owner of California or Arizona would probably worsen the discrimination that Mexican immigrants already experience on a daily basis in these states. Sadly, it is not impossible to imagine scenes of violence directed towards Mexican people and their property. Even if only for these reasons, the cons seem to outweigh the pros.

Yet the idea of Mexico revisiting the Treaty of Guadalupe-Hidalgo is not completely misguided. The approach and the extent of the demands just need to be different. Rather than seeking to annul the Treaty, Mexico could seek to fully enforce it. Indeed, the treaty is full of guarantees and promises of reparations from the U.S., the victor, to Mexico, the vanquished. Take, for instance, article VIII, which states that:

In the said territories (Alta California and New Mexico), property of every kind, now belonging to Mexicans not established there, shall be inviolably respected. The present owners, the heirs of these, and all Mexicans who may hereafter acquire said property by contract, shall enjoy with respect to it guarantees equally ample as if the same belonged to citizens of the United States.” (3)

Cuauhtémoc Cárdenas. Photo: El Universal. 

An expansive interpretation of this article, for example, could provide Mexico with political grounds to uphold the right to look after the material well-being of its citizens in the U.S. It also gives political ammunition to Mexico to counter the ongoing narrative of the current U.S. administration, and their desire to build a wall against their neighbour. The Mexican government can press an alternative narrative more in line with its interests: of two intertwined nations who share a long and wide border where their people coexist, and upon which both parties have interests and ought to collaborate for the benefit of North America.

(1) Miranda, Justino (2017, March 10). Promueve Cárdenas demanda para anular cesión de territorio a EU. El Universal. Retrieved from  Author’s translation.

(2) Engel, Pamela (2017, January 27). TRUMP: Mexico 'has taken advantage of the US for long enough'. Business Insider. Retrived from

(3) Treaty of Guadalupe-Hidalgo, February 2, 1848; General Records of the United States Government, 1778-1992; National Archives.


The views and opinions expressed in this
article are those of the author/s and do not
necessarily reflect those of the LARC.


Alejandro García Magos holds a PhD in Political Science from the University of Toronto. He is the author of “López Obrador in Democratic Mexico,” featured in the Oxford Research Encyclopedia of Latin American History. He has previous degrees from the Universidad Iberoamericana, in Mexico City, and the University of Calgary.