LAREDO, Texas — About 70 miles south of San Antonio along Interstate 35, well outside the city and its suburbs, the landscape spreads out into a flat expanse of prickly pear and palo verde populated mostly by cattle wandering vast ranchlands strewn with oil derricks. About halfway to the Texas-Mexico border from San Antonio is the small town of Cotulla, where a southbound traveler will begin seeing U.S. Border Patrol SUVs on the side of the freeway. Forty miles further south, on the northbound side of the interstate, sits a Border Patrol checkpoint. This is where things begin to change.

A majority of the traffic now consists of semi-trailers and other cargo vehicles, all of them headed for Laredo, where I-35 terminates at the Juárez–Lincoln International Bridge. The bridge, which carries private vehicles and pedestrians over the Rio Grande River, is one of four international crossings in this sweltering border city of 250,000 people. Most Americans have no idea that Laredo is the country’s largest land port of entry by volume, or that out of all U.S. ports of entry, both land and sea, it is second only to the port of Los Angeles.

Lately when Americans talk about the border, they rarely think of places like Laredo. Depending on their politics, they might think of a wall and a remote river, and of migrants and drug smugglers stealing across it. Or they might think of families cruelly separated by the federal government, corralled into detention facilities and lost in a bureaucratic nightmare.

They will think of these things largely because this is what President Trump tweets about and what the mainstream media tends to cover. These themes—border security and the family separation crisis—are shaping our national dialogue on immigration and the border. Recently, writing on Twitter, Trump threatened a government shutdown “if the Democrats do not give us the votes for Border Security, which includes the Wall! Must get rid of Lottery, Catch & Release etc. and finally go to system of Immigration based on MERIT! We need great people coming into our Country!”

Meanwhile, recent media coverage has focused on the Trump administration blowing a deadline to reunify families separated at the border. More than 400 migrant children are still in federal custody, their parents deported without them. Of those families that have been reunited, many are being held in federal detention centers in Texas, where the Trump administration is planning to house up to 15,500 migrants on military bases.

To be sure, border security and the family separation debacle are important aspects of the larger debate over immigration, but we often focus on them to the exclusion of what is arguably a much more important piece of the story, the thing that has driven people and goods back and forth over the Rio Grande for centuries: trade.

In Laredo, A Disappearing Border

Laredo is one of the few cities in America where you can wander around downtown and not have the slightest clue you’re in the United States. Judging from outward appearances, you might as well be deep in Tamaulipas, Mexico. Nearly every sign and advertisement is in Spanish, and nearly every person you meet will first address you in Spanish, which is as much the language of commerce and daily life in Laredo as it is across the river in Nuevo Laredo. According to the last U.S. Census, the city is more than 96 percent Hispanic, making it one of the least ethnically diverse cities in the country and one of the few smaller metros that have no de facto white or African-American neighborhoods.

Every day about ten thousand people walk across the Gateway to the Americas International Bridge from Nuevo Laredo to shop, work, and go to school. When they emerge from the Customs and Border Protection checkpoint on the American side of the bridge, many head toward nearby shops, some carrying collapsible shopping carts, which Mexican merchants use to load up on brand-name merchandise that will fetch a higher price in Nuevo Laredo—as long as they keep their loads small enough not to trigger custom duties upon reentry. Students come across to attend classes at Laredo Community College, where many study with scholarships from the Mexican government. And of course some Mexicans simply come over to visit friends and families, grab a bite to eat, or attend Mass at San Agustín Cathedral in the downtown historic plaza.

Unlike most border towns in Texas, Laredo pre-dates its Mexican counterpart on the south side of the river. San Agustín de Laredo, as it was called at its founding in 1755, was one of the last colonial towns of New Spain along the Rio Grande. Today, it’s the oldest independent settlement in Texas and the only remaining Spanish colonial town (as opposed to a mission or fort) north of the Rio Grande.

In the 1848 treaty of Guadalupe-Hidalgo, which settled the Mexican-American War, Laredo was ceded to the United States against the wishes of some residents, who petitioned the U.S. government to return the town to Mexico. When Washington refused, 17 families moved south of the river and established Nuevo Laredo. They even exhumed the remains of their ancestors so they could re-bury them on Mexican territory.

If they could see Laredo and Nuevo Laredo today, those families might reconsider. The complex interaction between Mexico and the United States reaches a kind of saturation point in Laredo. The city is more than just a Mexican version of Texas, which better describes the Rio Grande Valley about a hundred miles south down the river. Rather, Laredo is like a piece of Mexico inside of Texas.

It’s not just that almost everyone speaks Spanish, or that so many Mexican nationals live and work in the city, or that the cultural and commercial ties along the Texas-Mexico border go back centuries. That’s true of all of south Texas. Laredo is different because it is nearly impossible to tell where one country ends and the other begins.

The frequency of license plates from Tamaulipas, or the occasional political posters for Mexican president-elect Andrés Manuel López Obrador serve as subtle reminders that this is a true borderland. The not-so-subtle reminders are the ceaseless flow of cargo-laden semi-trailers roaring through the ports of entry, the hundreds of thousands of drivers and passengers and pedestrians that cross back and forth every day, the entire swirling and recursive exodus over and back across the Rio Grande, which at the end of the day is the only thing that really divides one country from the other here in south Texas.

But if you look closely, the river reveals a divide. You will not see families picnicking and fishing on the American side, but you will see them every day on the Mexican side: children playing in the water, men wading out to their waists with fishing poles, families cooking out and relaxing. One Border Patrol agent told me the reason for this is because in Mexico they won’t let the dangers of the river—the endless flow of drug mules and human smugglers—stop them from living their lives. They have accepted the risks.

It might also be because the direction of travel, whether of drugs or people, is south to north, which is also why not all the people you see on the south bank of the river are simply at their leisure. Some of them are what’s called halcónes—hawks or lookouts for the cartels, which also rely on Laredo for their trade.

A Constant Flow of Cargo, Legal and Illegal

Trade has long been Laredo’s raison d’être. In 1881, the railroad connected to the city, inaugurating an era of cross-border commerce that brought rapid growth to the town and transformed the region forever. Today, tens of thousands of commercial and private vehicles pass through Laredo every day, along with 100,000 passengers and pedestrians. More than $200 billion in trade comes through the city annually—a total that has been steadily increasing (in 2003, it was $80 billion).

Already this year, trade through the Laredo port of entry has exceeded $113 billion. More than half of all U.S.-Mexico trade passes over a single bridge in Laredo, the World Trade International Bridge, which handles commercial freight and sees more than 7,000 northbound 18-wheelers come across from Mexico daily.

By some estimates pieces of a new car or truck will cross the border eight times before it ends up on a showroom floor.

It’s not an exaggeration to say that the Laredo’s international bridges are like the pulsing veins and arteries of the U.S. economy—or that if the port of entry were shut down even for a day it would send shockwaves through international markets. Laredo would suddenly become a national priority.

At the Customs and Border Protection (CBP) inspection facility on the World Trade bridge, you’ll find every conceivable consumer good and commodity. On a recent Monday afternoon, trucks were lined up at loading docks and opened for inspection, carrying laundry detergent, partially assembled car seats, Tesla auto parts, bags of concrete mix, bundles of used plastic bottles, pallets of tequila, cases of chamomile tea, mangoes, broccoli, even packages of straw sold at pet stores.

Within a week of passing through customs, these goods will touch every part of the United States. The majority of goods are auto parts, often partially assembled. So intertwined are U.S. and Mexican auto manufacturing operations that by some estimates pieces of a new car or truck will cross the border eight times before it ends up on a showroom floor. Last year, the Mexican automotive industry set new records for production and exports, although numbers for this year have slackened amid uncertainty about negotiations to overhaul the North American Free Trade Agreement.

I met Javier Vasquez, CBP watch commander for Laredo, at a place he called “inspiration point,” where 15 lanes of northbound trucks creep bumper to bumper, all day long, toward CBP inspection stations. “Each year, the volume coming across here increases by three to five percent,” says Vasquez, adding that it’s been that way more or less since the bridge opened in 2000.

We drove past the waiting trucks, scores of which were open and waiting for an initial inspection in the 105-degree heat. Drivers loitered under a nearby pavilion waiting for clearance to pass through, in some cases for three or four hours. Vasquez tells me that most of these drivers simply deposit their containers at distribution centers in Laredo, re-enter Mexico, pick up another container at a distribution center in Nuevo Laredo, and make another trip. “They do as many as they can in a day,” he says. “That’s how they get paid.”

Customs and Border Protection has no way of knowing how much contraband is slipping past them at ports of entry.

A handful of lanes are reserved for drivers approved for CBP’s Free and Secure Trade (FAST) program, and they move much faster than the others. About a quarter of all northbound trucks passing over the World Trade bridge are part of this program, which expedites the process in return for more stringent vetting of drivers and companies. Short-haul drivers paid by the load have an especially strong incentive to enroll in the program. Vasquez and other CBP officials I spoke to expressed great confidence in it, although it’s easy to see how sophisticated drug cartels—or “transnational criminal organizations” in government parlance—might exploit such a program to avoid scrutiny.

The scrutiny these thousands of trucks and drivers do face is in many ways random. A mobile scanning unit will drive down a line of non-FAST trucks using a gamma-ray scanner to screen cargo for nuclear materials or weapons. A certain percentage of these trucks are then flagged for secondary inspection and sent either to loading docks or a giant X-ray machine for more detailed scanning.

At the loading docks, a K-9 unit goes into each container, and if the dog detects nothing, a certain percentage of merchandise is opened and physically inspected by a CBP agent. (To demonstrate this for me, Vasquez tore open a case of tequila and lifted a bottle out, carefully examined it, and put it back in the case.) For refrigerated containers hauling food, the inspected cargo—about 2 percent of each load—is simply discarded after inspectors rifle through it by hand. The shipping companies know this, and account for the loss when they initially load the trucks.

For as old-school and seemingly inefficient as these manual inspections are, the scanning station is something else entirely. From the outside, it looks like a car wash for 18-wheelers. The driver pulls in, gets out of the vehicle and waits in a separate building while the truck is scanned. A team of CBP officers operate the scanner, which uses high-energy X-rays generated by particle accelerators to reveal, in remarkable detail, the engine, tires, cab, and whatever’s in the shipping container—every nook and cranny is revealed in high-definition after a 30-second scan.

One agent told me he once found packages of marijuana hidden inside frozen avocado pulp, which he spotted on the scanner.

This is how CBP finds drugs hidden deep within a truck—in the tires, the gas tank, or a secret compartment squeezed between engine components. Over the past decade or so, concealment methods have improved considerably. Sometimes officers find contraband hidden deep within the cargo itself. One agent told me he once found packages of marijuana hidden inside frozen avocado pulp, which he spotted on the scanner. “It was a mess, we had to wait for it to partially thaw before we could pull out the marijuana.”

There is of course no limit to the ingenuity of drug smugglers, and the sheer number of commercial and private vehicles coming into Laredo guarantees that significant quantities of drugs—especially meth, heroin, and fentanyl, which are much easier to conceal than bulky packages of marijuana—will get through. Liquid meth, for example, can be dissolved in a tank of gasoline. Just as the Border Patrol has no way of knowing how many people are illegally crossing the border, CBP has no way of knowing how much of this contraband is slipping past them at ports of entry.

Based on what they do intercept, it’s probably quite a lot. In recent years, the most common contraband has been meth. On average, customs officials in Laredo seize a large quantity of meth (more than 50 kilos) every 72 hours. The day before I visited the Juárez–Lincoln International Bridge, CBP made two separate seizures of meth that together were worth nearly $3 million. The first was 104 pounds of liquid meth hidden in a Chevy truck, the second was 110 pounds of crystal meth hidden in a Dodge SUV. Seizures of this scale, rare almost anywhere else in the United States, are normal in Laredo, where drugs always come through in bulk and are always deeply concealed.

Land Ports Of Entry Pose A Massive Challenge

CBP’s Laredo operation is impressive because of its sheer size and scope, but the inescapable reality is that goods coming over from Mexico face far less scrutiny than sea-borne cargo coming from China or elsewhere overseas. Major U.S. land ports of entry like Laredo are woefully outdated and underfunded, with technological features (like X-rays) overlaid on what is essentially a crumbling infrastructure.

That stands in contrast to how the U.S. handles cargo coming from overseas: manifests are submitted to U.S. authorities before the ships ever leave the dock in their country of origin. In Laredo, CBP only gets a manifest about an hour before a truck shows up at the crossing.

Goods coming over from Mexico face far less scrutiny than sea-borne cargo coming from China or elsewhere overseas.

The same is true of pedestrians walking over from Mexico on the Gateway to the Americas International Bridge. They face far less scrutiny than international travelers flying into U.S. airports. After all, airline passenger manifests are submitted to U.S. officials prior to takeoff, so if any names raise security concerns the passenger in question can be removed before the plane departs.

In Laredo, thousands of Mexican nationals simply show up every day, most of them with a border crossing card, good for ten years, that allows them into the country for 72 hours but restricts how far inland they can go. The cards are scanned briefly by CBP officers and the travelers are waved through, one after another. On any given weekday, the flow of people coming in is constant, and with only about a dozen turnstiles and officers working the bridge, each traveler gets only a cursory check.

This is the bridge where families or individuals from countries other than Mexico will typically present themselves to CBP and request asylum. Lately, the plight of Central American families applying for asylum has caught the national media’s attention, with families being stopped at the midway point of the bridge and told to wait by CBP officers claiming the facility was at capacity.

This claim met incredulity from many press outlets that probably have no idea what CBP’s facilities are actually like at this bridge. Not only is there a shortage of officers to handle asylum claims—because most of them are busying shuffling thousands of Mexicans with border-crossing cards through turnstiles—there is also a woeful shortage of places to process and hold asylum-seekers.

The flow of people coming in is constant, and with only about a dozen turnstiles and officers working the bridge, each traveler gets only a cursory check.

I walked through these facilities with Jesus Barrera, chief of staff for the Laredo port of entry, who told me that when his officers tell families on the bridge that they can’t process asylum-seekers on a given day, they’re not lying. I soon understood why. The secure area set aside for asylum-seekers is remarkably small: a low-ceilinged rectangular room with a row of tables and computers where CBP officers can conduct interviews.

About a half-dozen detention rooms line one wall of this main room. They are also small, about nine by 12 feet, with a steel bench and a lavatory, rather like a prison cell. The morning I was there, three families—two mothers with one child each, and a father with a daughter—occupied three of these rooms. They were sleeping on blue foam mattresses on the floor. A young girl peered out at us from a window on the door of her room as we walked by. One man, a Honduran, was being interviewed by a CBP officer. At most, this area could hold maybe 20 or 30 people.

‘This Is Not Ever Going To Stop’

The border is always stranger than you expect it to be. And it is never the same from place to place. Here in Laredo there’s been a sudden and inexplicable surge of illegal immigrants from Bangladesh. In 2016, one Bengali was apprehended in the Laredo sector. The next year there were more than 170, and so far this year there have been 473.

No one can say for sure why these Bengalis have turned up now, or why they have turned up specifically in Laredo. Yet here they are, some of them having reportedly paid cartels upwards of $27,000 to be smuggled into the United States.

Most of them claimed to be Sikhs facing religious persecution in the Indian states of Punjab and Gujarat, which experts said didn’t make much sense.

But of course this isn’t the first time south Texas has seen waves of migrants from far-flung places. In the past it has been Brazilians or Chinese. In 2011, thousands of Indians illegally crossed in the Rio Grande Valley as part of a complex human-smuggling pipeline that appeared suddenly, baffling U.S. border authorities. Most of them claimed to be Sikhs facing religious persecution in the Indian states of Punjab and Gujarat, which experts said didn’t make much sense since Sikhs hadn’t been targeted in those areas since the 1980s.

With all these nationalities, the pattern is largely the same: fly into a South American country that doesn’t scrutinize international travelers all that much, make your way north to Guatemala, sneak across to Mexico and travel by vehicle to the U.S. border, paying smugglers as you go. In this way, at different times and in varying numbers, just about the whole world eventually shows up on the Texas border.

Although Laredo has not seen the dramatic increase in illegal immigration that’s hit the Rio Grande Valley in recent years, it remains one of the busiest sectors on the southwest border, with 25,460 apprehension last year, the vast majority of them adult men. It’s also one of the most dangerous sectors, second only to the Rio Grande Valley in 2017 for rescues and deaths (1,054 and 83, respectively).

Most often, the danger comes from exposure, especially in the heat of summer. On Monday, five men attempting to evade a Border Patrol checkpoint were rescued after they got lost somewhere northwest of Laredo and called 911 in desperation, likely because they were out of water. A substantial number of deaths come from drownings in the Rio Grande, which can look deceptively calm despite its strong currents.

‘He told me that he was safer in custody here, and he was closer to his family. His family at least could see him in custody.’

The Border Patrol’s riverine units patrol daily in Laredo, often assisting in water rescues of migrants who attempt to cross where they shouldn’t, or drug smugglers who try to cross with heavy packs. Drowning deaths on the southern border have been on the rise in recent years, even as the total number of migrant deaths has been underreported.

Given these dangers, large numbers of migrants will try their luck at the ports of entry, either by hiding in passenger vehicles or paying to be smuggled across in commercial vehicles, a tactic that presents its own unique danger.

But whether it’s drowning in the river, exposure to the elements, suffocating in a truck or risking capture at a border crossing, none of it is much of a deterrent. Raul Martinez, a federal public defender in Laredo, told me he once had a client from Mexico who had been arrested multiple times for illegal reentry but refused to stay away. “He told me that he was safer in custody here, and he was closer to his family. His family at least could see him in custody, and he wouldn’t stop coming because that was the only way he could be close to his family and he could be safe.”

I asked Martinez and his colleague, Marissa Perez-Garcia, what they wished people in other parts of the country understood about the southern border and illegal immigration. They were silent for a while and then Perez-Garcia leaned forward and slowly said, “This is not ever going to stop. There is no way to stop it. People will find a way to come because their need is greater than their fear. It’s greater than the consequences that they’re going to face.”

Much the same could be said about the trade, legal and illegal, that courses through places like Laredo. Trade is after all nothing but human activity and ambition, channeled into countless enterprises and transactions. The people coming across the border can no more be stopped by a wall than the freight coming across can be stopped by tariffs. People and goods will come because of demand and desire and necessity. There is no way to stop it.