Considering History: Myths and Realities of the Mexican-American Border

Many imagine the border between the U.S. and Mexico to be a consistent, stable entity, but history shows that this line – and the many debates that surround it – is prone to revision.

A U.S. Border Patrol car driving along the Mexican-American border

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This series by American studies professor Ben Railton explores the connections between America’s past and present.

The federal government shutdown dominating the headlines as 2019 begins is entirely connected to one specific, controversial issue: America’s southern border with Mexico. Although the question of funding for President Trump’s proposed wall has been the overt focus of the debate, Trump’s Tweeted threat to “close the Southern border entirely” if a deal is not negotiated makes clear just how fully the border itself has become a pawn in this contentious moment.

There are various complex legal and social issues associated with the border, including whether and how arrivals should be able to apply for asylum, what to do with asylum seekers while they are awaiting those decisions, and what role various federal agencies should play in these processes. But as with so many contemporary debates, unless we can better understand the historical realities that underlie our mythic understanding of the Mexican-American border, those current conversations will necessarily be incomplete.

The most foundational such myth is that the border between the two nations has been a consistent, stable entity. It’s an understandable belief, given that Mexico and the United States have established political and geographic boundaries, and the diplomatic relationships that stem from them, in the 21st century. But the earliest histories of the Mexican-American border reveal not only that it was entirely constructed and malleable, but that the contest over where and how it would be defined shaped both national identities and their relationship to one another.

The 1846-48 Mexican-American War centered directly on that border dispute. The Texas Republic had been independent since its 1836 war with Mexico, and in December 1845 the United States annexed Texas and made it the nation’s 28th state. At the same time, newly elected President James Polk was seeking to purchase land from Mexico and to set the border between the two nations significantly farther south, at the Rio Grande river. When Mexico refused these offers, Polk disregarded Mexican sovereignty and borders, moving U.S. troops into the Mexican region known as the Nueces Strip. Farther west, Polk sent explorer John Frémont and a group of armed men into the Mexican province of Alta California, where Frémont raised an American flag over his fort on Gavilan Peak. Mexico responded predictably to these overt intrusions into its territories, moving its own forces into the disputed regions and skirmishing there with U.S. troops, and the war between the two nations began.

Map depicting the extend of the United States of Mexico in 1824, showing how Mexican territory extended north to Oregon.
Mexican territory in 1824. (By Giggette / Wikimedia Commons)

The 1848 Treaty of Guadalupe Hidalgo that cemented the U.S. victory in that war—a treaty negotiated quite literally at gunpoint and without Polk’s knowledge, while U.S. troops were occupying Mexico City—thus did more than cede vast swaths of Southwestern and Western territory to the U.S. It created an entirely new border between the two nations, one in which not only the Nueces Strip and Alta California but much of the rest of the Southwest were suddenly located on the American side. Those areas were still populated by millions of Mexican citizens, however, inhabitants and communities whose ambiguous and fraught new status as Mexican American citizens (a status promised by the treaty, yet highly contested by Anglo settlers) reflected one more layer to the new border’s artificial nature.

Painting of United States General Winifred Scott entering Mexico City with his army in the waning days of the Mexican War.
General Winfield Scott entering Mexico City in the Mexican-American War. (Adolphe Jean-Baptiste Bayot / Wikimedia Commons)

So the Mexican-American border came into existence in a contested, controversial, constructed way that produced communal uncertainty for many decades to follow. Ironically, that border also remained entirely open and unpatrolled. Indeed, for half a century after the treaty, the U.S. maintained no presence of any kind on the border, and residents of both nations (and anyone else who found themselves there) could move freely back and forth across it.

The first federal officials to patrol the Mexican-American border did so in the first decade of the 20th century, and in a very targeted and telling way. Numbering around 50-75 at a time, these “mounted guards” (employees of the Department of Commerce and Labor) operated out of El Paso and were tasked solely with watching for Chinese immigrants, the only arrivals defined as illegal in the era. When Congress formalized the guards in the aftermath of the discriminatory Immigration Act of 1917, they likewise emphasized their role in watching for the Asian arrivals (now including many nations within an “Asiatic Barred Zone”). From the outset, these guards existed not to enforce the border and its rules for all arrivals, but to target particular communities defined as undesirable under a bigoted legal system.

A U.S. Border Control vehicle drives along a fence on the Mexican-American border.
Patrolling the border between the U.S. and Mexico.

It is thus no coincidence that the U.S. Border Patrol was created as an agency within the Department of Labor in 1924, the same year of the Immigration Act of 1924 (also known as the Johnson-Reed Act), which established discriminatory national quotas that affected most arrivals to the United States. These border guards continued to serve in a targeted role, looking for arrivals within those affected national categories (and, at the Canadian border in particular, for illegal alcohol smuggling under Prohibition). Moreover, since nations in the Western Hemisphere were originally exempt from the 1924 law’s quota system, Mexicans (for example) could continue to move freely across the border and into the United States, reflecting just how arbitrary the power of both the border patrol and the border itself were.

Immigration laws and realities have evolved greatly in the century since those 1924 laws; now it is Western Hemisphere arrivals who are most consistently restricted by our immigration categories and preferences, and thus most often targeted by the border patrol. These contemporary laws represent an unfolding legacy of the contested history of the Mexican-American border, a history that belies many of our myths and likewise demands deeper understanding and engagement.

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  1. PS. Since there’s so much more to say about these histories than I was able to here, a couple of sources for further reading and conversation:

    –Maria Amparo Ruiz de Burton’s historical novel *The Squatter and the Don* (1885) details Mexican American life after the Treaty very fully. See for example Chapter 2:

    –And Carey McWilliams’ *North from Mexico* remains a really great history of Mexican Americans and the border, including lots about the post-1920s histories I wasn’t able to get to in this piece. Here’s an excerpt:


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