On an August afternoon in 1918, a mysterious man approached the U.S.-Mexico border in the bustling town of Nogales.
For decades, the boundary between the two countries had been little more than an imaginary line in the sand, marked only by the occasional — often crumbling — pillar in the Sonoran desert. But rampant smuggling, the Mexican Revolution and the outbreak of World War I had split the border town in two, sowing fear and stoking tensions.
As the man walked toward Mexico, where Mexican soldiers were waving him on, a U.S. Customs inspector suddenly ordered him to halt.
Unheeded and suspecting the man was a smuggler, the customs inspector drew his gun.
So did two American soldiers, one of whom would later say he thought the man was one of the many German spies rumored to be trying to draw Mexico into war with the United States.
Yards away, Mexican officials also shouldered their rifles. When one fired, hitting an American soldier in the face, both sides of the border erupted in gunfire.
“A battle breaks out, killing 12 people, including the mayor of Nogales, Sonora,” said Rachel St. John, a history professor at the University of California at Davis who wrote about the incident in her 2012 book, “Line in the Sand: A History of the Western U.S.-Mexico Border."
The two-hour shootout marked the end of an era of easy movement across the boundary in Nogales, she said, as Mexican and American officials quickly agreed to put up a six-foot fence through the middle of the border town.
Today, the fence is now a 20-foot-high row of steel beams, recently reinforced with razor wire.
On Thursday, President Trump traveled to the border to demand $5.7 billion funding for a wall, a high-stakes visit that draws attention to the past century of wild, often unsuccessful efforts to fortify the U.S.-Mexico frontier.
Long before the perceived threat was Central American asylum seekers, it was German spies and Mexican revolutionaries, prostitutes and polygamists, Chinese immigrants and cattle infected with “Texas fever."
‘A symbolic boundary’
“The border between Mexico and the United States is not just a line on a map,” wrote sociologist Douglas Massey in a 2016 essay. “Rather, in the American imagination, it has become a symbolic boundary between the United States and a threatening world. It is not just a border but the border, and its enforcement has become a central means by which politicians signal their concern for citizens' safety and security in a hostile world.”
Given this outsized importance, Massey wrote, it is easy to forget that the U.S.-Mexico border didn’t exist at all until 1821, when Mexico gained independence from Spain. And it wasn’t for another 30 years that the boundary line looked anything like it does today.
Texans revolted against Mexico in 1836, largely to preserve the institution of slavery, according to Massey. When Texas joined the Union in 1845, it led to a war between the United States and Mexico that ended with American troops occupying Mexico City. At gunpoint, Mexico signed away what is now Arizona, California, Nevada, New Mexico, Utah and Colorado for $15 million. Five years later, in 1853, the United States bought another 30,000 square miles for $10 million so that it could build a transcontinental railroad.
If the two treaties fixed the U.S.-Mexico border on a map, they did little to clarify things on the ground.
By the end of the century, the boundary was blurred beyond recognition. Markers had been moved, destroyed or vandalized. Towns had sprung up on the border. In Nogales, saloons straddled the border, selling Mexican cigars on one side and American liquor on the other, both duty free, St. John wrote.
In 1882, the United States and Mexico formed a joint commission to resurvey, remap and remark the border. The team found that in one stretch, there wasn’t a single marker for 100 miles.
“This ambiguity, noted the commissioners, was 'giving rise to many disputes between miners, farmers, and herders, and permitting every facility and encouragement for smuggling,” St. John wrote.
Officials on both sides of the border began trying to impose order — and fees. When a U.S. surveyor determined a Mexican man’s ranch crossed the boundary, the rancher was ordered to pay American taxes, too, St. John wrote. When the rancher couldn’t pay, he was arrested.
On the commission’s recommendation, President William McKinley ordered a 60-foot swath cleared along the Nogales border in 1897. Saloons were destroyed or moved. Ten years later, the order was extended to all of Arizona, New Mexico and California.
As the border began to take shape, officials started to restrict who and what moved over it. In 1909, Congress passed the Act to Prohibit the Importation and Use of Opium for Other than Medicinal Purposes, effectively launching the business of drug smuggling on the border, St. John writes.
That same year, the first federally built fence went up along the border in Baja to prevent American cattle from contracting “Texas fever”: a disease spread by ticks that had been nearly eradicated in the United States but persisted in Mexico.
Around the same time, customs officials began to prevent the entry of certain people into the United States.
“While Mexicans and Americans moved freely back and forth across the boundary line, by the late nineteenth century a series of new U.S. laws restricted a growing number of immigrants from crossing the border,” St. John wrote. “The U.S. Congress passed the first law restricting immigration — specifically that of convicts and prostitutes — in 1875. By 1910 new legislation had added Chinese immigrants, lunatics, people likely to become public charges, contract laborers, polygamists, anarchists, and others deemed undesirable to the list of excluded groups. This legislation turned what had been an innocent movement of people into illegal immigration.”
The Bureau of Immigration was created at the turn of the century to crack down on all types of illegal entries, but its 18 agents were so consumed with catching undocumented immigrants from China that they quickly became known as “Chinese inspectors,” according to St. John.
Sophisticated smuggling networks soon developed along the border, including doctors specializing in removing “signs of disease,” corrupt officials and rail cars full of Chinese immigrants.
“Fences actually work way better for cattle then they do for humans,” St. John told The Post.
But like today, the journey then could be dangerous. In a preview of the violence that now marks migrants' routes through Mexico, a group of 16 Chinese migrants each paid their smugglers $100 to cross into the United States. Instead, they were murdered, their bodies found days later in a desert canyon by an inspector on horseback.
‘Sedition, conspiracy, plots and intrigue'
By the early 20th century, the border had become recognizable — if still easily crossed without detection. But that began to change with the outbreak of the Mexican Revolution in 1910.
As Mexican revolutionaries plotted from American hotels and battles spilled over the border, the United States struggled to remain neutral. Several American sentries were killed by stray bullets and refugees began flowing north. Both Mexican bandits and soldiers started raiding towns in the United States.
During the Battle of Sonora in 1914, the fighting came so close to the border that U.S. troops marked the boundary line with American flags to prevent it from spilling over, according to St. John.
It didn’t always work. On March 9, 1916, after the United States broke its neutrality by supporting one of Pancho Villa’s rivals, the Mexican general retaliated by raiding the border town of Columbus, N.M. Although Villa lost more than 100 men, compared to 17 Americans, one local described the scene as a “holocaust.”
“Main Street was in chaos,” Mary Means Scott recalled, according to “Line in the Sand.” “Men were frantically digging in the smoldering ruins for bodies. Others looked distractedly at yesterday’s places of business, now blackened junk.”
A week later, Gen. John “Black Jack” Pershing led an armed expedition into Mexico to catch Villa. The pursuit lasted for almost a year, and stoked Mexicans’ fears that the United States intended to annex its weakened southern neighbor.
As the United States was pulled toward entering World War I, American anxiety over the Mexican Revolution was compounded by fears of espionage along the border. In a telegram decoded by the Americans in early 1917, the German foreign secretary offered Mexico support “to reconquer its former territories.”
Two years earlier, a plot had been discovered to do just that, said Miguel A. Levario, a history professor at Texas Tech University and the author of “Militarizing the Border: When Mexicans Became the Enemy.”
“There was some concern that Pancho Villa would give an order and all the people of Mexican descent [in the United States] would overtake Fort Bliss,” Levario told The Post. But the so-called Plan de San Diego didn’t get very far before its alleged mastermind was arrested.
“When the guy was brought to trial, the judge thought it was such a ludicrous idea that he thought guy didn’t need jail time but rather a psychiatrist,” Levario said.
Still, fear lingered.
“If the people of Los Angeles knew what was happening on our border, they would not sleep at night,” the Los Angeles Times warned in April 1917, according to “Line in the Sand.” “Sedition, conspiracy, plots and intrigue are in the very air. The telegraph lines are tapped, operators have been seduced with gold and spies come and go at will.”
This was the atmosphere on the afternoon of Aug. 27, 1918, when the mysterious man approached the border in Nogales.
“We still don’t know who he was,” St. John told The Post. “Maybe he was a spy. Maybe he was a smuggler.”
What was clear was the response, as Mexico and the United States agreed to erect a six-foot fence.
Other fences went up along the frontier around the same time. Near the border between Calexico and Mexicali a year later, two U.S. soldiers fatally shot a Mexican man named Alfredo Valenzuela only for investigators to find they weren’t sure in which country the killing had occurred.
“To determine if Valenzuela was shot on U.S. soil they had to call in an engineer to determine the location of the boundary,” St. John wrote. “Noting the need to clearly demarcate the boundary line given the heightened border controls, [Baja] Governor [Esteban] Cantú suggested the U.S. government build a fence to assure that its soldiers knew which side someone was on before they shot.”
Even after the end of World War I and the Mexican Revolution, some of the border fences stayed up, according to St. John.
“By the early 1920s, there are what look like permanent fences maintained by the government at most major ports of entry,” she told The Post.
Over the next century, these wood and barbed wire fences would be upgraded to chain link — including some from Japanese internment camps, according to St. John — and then, in the 1990s under both George H.W. Bush and Bill Clinton, to 12-foot metal sheets formerly used as helicopter landing pads during Vietnam.
Although these measures were met by local protests, they enjoyed broad bipartisan support. When George W. Bush signed the Secure Fences Act into law in 2006, authorizing the construction of 700 miles of new border fencing, 80 senators supported it including Hillary Clinton, Barack Obama and Charles E. Schumer.
Yet, St. John warned against equating fence-building a century ago to Trump’s demand for a wall today.
“When they were building fences in Nogales during the Mexican Revolution, it was a response to what was happening along the border,” she said. “That is not what is happening now. This [demand for a wall] is coming top down. It is entirely divorced from the reality on the ground.”
Correction: Gen. Pershing’s pursuit of Pancho Villa lasted almost one year, not two.
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