Loren Elliott / Reuters

The U.S.-Mexico border has been a humanitarian challenge for years, throughout the Clinton, Bush, and Obama administrations. Now, the rapidly shifting policies of the Trump administration have placed the matter once again at the forefront of the nation’s attention. In a recent conversation about family separation, one of our members asked us to take a wider look at the issue. The member asked, how did the U.S.-Mexico border, now occupying what was once Mexican territory, end up where it is today? Rachel St. John, a professor of history at UC Davis who specializes in the U.S.-Mexico border, joined us on the forums to discuss these questions. We’ve included edited versions of her answers below, followed by a brief dive into The Atlantic’s history of coverage of the border region.

—Caroline Kitchener  

A Brief History of the Border

Why is the U.S.-Mexico border so conflict-ridden? [Forum post here]

St. John: The U.S.-Mexico border has been among the most contentious international boundaries in the world. This tension stems from the divergence between the U.S. and Mexican economies, from issues related to immigration and drug-trafficking, and from a historical relationship in which Americans and the United States government have often intervened in Mexican affairs to protect their own interests.

Since the late twentieth century, the U.S.-Mexico border has also been the focus of a great deal of political debate and acrimony within the United States which has made the border significant as a symbolic political site. However, although political rhetoric focuses on border conflict, throughout their history, the United States and Mexico have more often been allies than enemies. The two nations’ economies are tightly integrated and have been since the nineteenth century. The millions of people, cars, buses, trucks, and airplanes that cross the border every year dwarf the numbers of unauthorized entrants on which so much political debate focuses.

How was the border decided? [Forum post here]

The white area indicates the territory ceded by Mexico to the United States in the Treaty of Guadalupe Hidalgo. The brown area indicates the territory conferred to the U.S. in the Gadsden Purchase (United States Federal Government).

St. John: U.S. and Mexican officials negotiated the boundary line during the U.S.-Mexican War—as United States forces invaded Mexico. President Polk had gone to war with Mexico to acquire more territory in western North America, particularly California. (The United States government had previously made multiple attempts to buy territory from Mexico, but Mexico had refused to sell.) During the war, U.S. troops seized control of Mexican outposts in New Mexico and California and invaded Central Mexico, enabling the U.S. government to demand vast land cessions from the Mexican government.

Americans were politically divided about the acquisition of Mexican territory. Some Americans believed it was wrong to wage a war of conquest. Others thought that it was necessary. Yet others, including President Polk, wanted the United States to acquire even more territory from Mexico—perhaps even the entire country! In light of these diverse opinions, the final boundary line was a result of both specific U.S. expansionist desires and the contingencies of negotiations. The original boundary was revised in 1853 by the Gadsden Purchase.

In the more than a century and a half since then, U.S. and Mexican officials have negotiated over small inaccuracies and changes in the position of the boundary line, but the main position has remained the same.

What myths have shaped the history of the U.S.-Mexico border? [Forum post here]

St. John: Probably the most significant “myth” about the U.S.-Mexico border is the myth of “Manifest Destiny”—that is, the idea that God intended the United States to take over Mexican territory. This has long prevented many Americans from honestly assessing the role that politics and territorial greed played in shaping the nation, and from acknowledging that U.S. growth came at the expense of Mexico, as well as the Native people who inhabited North America.

On the other hand, from a Mexican perspective, the emphasis on blaming the United States has at times caused Mexicans to overlook their own nation’s role in conquering territory from Native people. By framing the conflict as solely between the United States and Mexico, it is too easy to lose sight of the fact that the territory the United States conquered in the U.S.-Mexico War was inhabited and claimed by Native people.

How the Border Has Evolved in Recent Years

By Caroline Kitchener

In each of the past two decades, Atlantic writers have gone to the U.S.-Mexico border as policies in the region have changed. Their stories trace a clear and striking arc, showing how border crossings, immigration policy, and law enforcement have entangled over the years to amplify the current crisis.

  • 1992: One year before the North America Free Trade Agreement (NAFTA) passed, ushering in a period of unprecedented legal and illegal immigration, William Langewiesche reported on the ease with which Mexicans were able to cross into and out of the United States. He described a border that was highly porous, with Mexicans incentivized to take advantage of economic opportunities in the U.S., while retaining the ability to return home. While some Mexicans may be turned away at first, he wrote, “anyone who tries [to cross the border] will eventually succeed.” The Immigration Reform and Control Act of 1986 had done little to dissuade those eager to start a new life in the United States, he said. Langewiesche recounted making eye contact with one member of a group of young boys crossing the border wall in San Ysidro, California. “He wanted me to understand that he was unafraid. To prove it, he turned and dropped through a full backflip, ten feet down into the United States.”

  • 2005: Marc Cooper described a border region far more trafficked than it was in the early nineties. “By the 1993 passage of the North America Free Trade Agreement, only about 2.5 million undocumented Mexicans were living in the United States,” he wrote. “Since then, by conservative estimates, the number has more than doubled.” (Today, that number is estimated to be almost 12.5 million unauthorized immigrants.) But while security had tightened considerably, Cooper said, Mexican immigrants were not deterred, continuing to seek passage by any means necessary. “One thing is for certain: Those battered vans in Altar will continue to load up every afternoon, and every evening, their human cargo will find a way across the border.” The only way to halt illegal immigration to the United States from Mexico, Cooper said, quoting Tucson-based journalist Charles Bowden, would be to fundamentally change the U.S. economy, and “lower U.S. wages to the same level as Vietnam.”

  • 2018: Jeremy Raff, a video producer at The Atlantic and a Rio Grande Valley native, has been reporting, and capturing powerful video, from the border region. Most recently, he’s followed the stories of families separated in the wake of the Trump administration’s “zero-tolerance” border crackdown. Raff interviewed parents who fled violence in Central America, not realizing until they arrived in the United States that crossing the border, and being separated from their children, would cause “‘much greater suffering’ than the original violence.” Still, other Atlantic reporters have written, given what people are fleeing, it’s unlikely that even brutal approaches such as family separation could effectively deter illegal immigration. “Many people are quite willing to risk their lives and the lives of their children to come to America,” Atlantic senior editor Krishnadev Calamur told The Masthead. “They do it for a reason. And I’m not sure that this kind of policy, however draconian it might seem to us, would actually deter people from coming to the United States.”  

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