Donald Trump’s campaign to deter illegal immigration by separating children and parents at the border began with an Easter morning tweet, after Fox & Friends showed a caravan of Central American families traveling through Mexico to escape gang violence at home. “NEED WALL!” he fumed. In the three-day eruption that followed, he blamed congressional Democrats, Barack Obama, and the Mexican government for the influx, while threatening to pull out of NAFTA and cut off aid to Honduras. Though illegal crossings rose this spring, they have generally been decreasing: last year the number of people apprehended at the border fell to a forty-six-year low. Three days after Easter, Trump announced that he was summoning the National Guard.

Soon after, Attorney General Jeff Sessions unveiled a new plan of “zero tolerance” that vowed criminal prosecution of all migrants caught crossing between border posts, including first-time offenders who had previously been handled in civil proceedings. While Sessions didn’t explicitly endorse the division of families, his actions made child separation official policy, even for many families seeking asylum, since children can’t be housed in criminal detention. “If you don’t want your child separated, then don’t bring them across the border illegally,” Sessions said. Since October, authorities have seized nearly three thousand children, including infants and toddlers, and sent them to foster homes in states as far-flung as New York and Michigan, leaving their frantic, incarcerated parents trying to figure out where they were. Some were deported without their kids. Given the violence the families were fleeing, this amounted, as one advocate put it, to “punishing parents who are trying to save their children’s lives.”

It wasn’t just liberals who cried foul. Thirteen Republican senators labeled the policy an affront “to ordinary human decency.” Laura Bush called it “cruel” and “immoral.” The Chamber of Commerce said, “This is not who we are.” The pro-Trump evangelist Franklin Graham found the effort “disgraceful.” The American Academy of Pediatrics denounced its “sweeping cruelty” and warned that taking children from their parents could inflict lifelong harm.

As the outrage mounted, Trump simply lied—he called family separation a Democratic policy. Sessions quoted the Bible. On Fox, Ann Coulter suggested the wailing children were “child actors,” and Laura Ingraham defended juvenile detention centers as “essentially summer camps.” Ultimately Trump retreated, suspending the policy days before a federal judge ordered the families reunited, and chaos reigned as officials tried to identify and return children, in some cases after having destroyed vital records. A week after the July 10 deadline to return children younger than five years old, only about half of them were back with their parents. The episode—which hundreds of Sessions’s fellow Methodists, in a complaint to the church’s governing body, likened to “child abuse”—marked a major escalation of Trump’s efforts to halt immigration and punish immigrants.

Lauren Markham is everything that Donald Trump is not—empathetic, honest, painstakingly factual, thoughtful, and fair. Her beautifully written book, The Far Away Brothers, follows Ernesto and Raúl Flores, seventeen-year-old twins, from a Salvadoran village ruled by gangsters from MS-13 to a high school in Oakland, where she served as their counselor. It can be read as a supplement to the current news, a chronicle of the problems that Central Americans are fleeing and the horrors they suffer in flight. But it transcends the crisis. Markham’s deep, frank reporting is also useful in thinking ahead to the challenges of assimilation, for the struggling twins and many others like them.

As it relates to the border crisis, the story reinforces the liberal view: the boys, who arrived in the US in 2013, are running from violence, not just poverty. They are more like refugees than economic migrants, though legally they don’t qualify for refugee status. They’ve been through hell. But they are not the striving overachievers that supporters of immigration tend to envision. Their harrowing journeys have left them traumatized. They are volatile, distrustful, and depressed. Both screw up in school, neither learns much English, and one drops out and becomes a teenage parent. People wary of immigration could read the story as a cautionary tale of its risks and costs.

It is a testament to Markham’s narrative skill that she keeps the reader pulling for her troubled characters while faithfully recording their blunders. They are just teens—two young men courageous enough to run from gang violence rather than join it. While they arrive in the US with the wounds of their journey, they also bring a ferocious work ethic. Markham’s reporting is intimate and detailed, and her tone is a special pleasure. Trustworthy, calm, decent, it offers refuge from a world consumed by Twitter screeds and cable news demagogues. The Far Away Brothers is a generous book for an ungenerous age.

Ernesto and Raúl are peasant boys, raised in a family of nine siblings so poor that sometimes food runs short. (The names are pseudonyms.) Four other siblings died as infants. Their father, Wilber Sr., is loving, religious, but old-school rough: “He’d wallop them so hard they’d be afraid of where the beating might end.” Everyone knows there’s opportunity up north. When the boys are eleven, their father borrows money to send one of his older sons across the border. Wilber Jr., who is “starry-eyed” at the prospect of American wages, makes the trip and becomes a hermano lejano—a faraway brother. He settles in California and pays off the coyote—the smuggler who helped him cross—but he rarely sends money home.

The country he leaves behind is increasingly ruled by gangs. By 2015, the murder rate reaches a level more than twenty times higher than in the US—even higher than it was in the 1980s during the Salvadoran civil war. “Heads were cut off, the corpses left out in the center of towns for all to see,” Markham writes. “Bodies turned up sprayed with so many bullets that practically none of the torso remained.” In all but name, El Salvador is at war again.

The violence closes in on the boys. When they are ten, a cousin is shot. When they are eleven, an uncle’s mutilated body is fished from a river. At twelve, they flee a squad of armed men who suspect them of supporting a rival gang. Schoolmates taunt them as “dark-ass peasant boys” who are “too poor for shoes.” The boys’ oddity as identical twins, and the family’s poverty and low social status, make them targets of aggression. Older kids in MS-13 urge Ernesto to join for protection. This may be less an invitation than a threat.

While Wilber Jr.’s motive for emigrating was mostly economic, the twins literally run for their lives. Their menacing uncle, Agustin, is a plantation owner and moneylender in cahoots with MS-13. Agustin scorns the twins’ poor, weak family. When someone chops down a favorite tree, his suspicions fall unjustly on Ernesto. “I’d like to crush that boy’s face in with a rock,” he says. Ernesto had already started to plot an escape to the US, but now he really needs to go. His father borrows $7,000 against his land to hire a coyote, and Ernesto slips away. As his brother’s lookalike, Raúl could easily be killed in his place; the family takes out another loan, and he flees nine days later.

What has gone wrong in El Salvador? The question invites a fuller treatment that Markham provides, but even her brief account makes clear that the US bears some responsibility. In El Salvador, the Reagan administration backed a brutal right-wing government notorious for its death squads in a cold war struggle against leftist insurgents that sent 350,000 people fleeing to the US. The country’s gangs were born in Los Angeles and sent back with deportees to El Salvador, a country where war had normalized violence and left civil authority weak.

The history explains how migration often works. People who see an immigrant “invasion” imagine the US as a passive target. But migration follows lines of global engagement, such as trade, investment, and war. Seven of the ten largest immigrant groups (Filipinos, Salvadorans, Vietnamese, Cubans, Dominicans, Koreans, and Guatemalans) come from countries the US invaded or where it had a large military presence—eight if you go back far enough to count Mexico. Salvadorans are here in part because of what we did there. “We have played a major part in creating the problem of what has become of Central America,” Markham writes.

The twins’ journey north is a nightmare. Ernesto watches his smugglers murder another migrant by slashing him with a machete and shooting him in the head. He stumbles across a headless corpse in the Texas desert, and his hands sink into the “wet, sickly mess.” Raúl is caught by Agustin’s henchmen, who tie him up, beat his driver, and rape his coyota. It was “sheer luck that he wasn’t dead.”

Trump’s officials (like President Obama’s) have tried to dissuade migrants by emphasizing the danger of the trip. “Don’t risk your lives or the lives of your children by trying to come to the United States on a road run by drug smugglers and human traffickers,” said Vice President Mike Pence. But Markham’s reporting suggests the migrants largely know what they’re up against. Everything that Raúl had “heard about the journey north was about its perils: thieves and rapists and killers.” He is convinced “that the worst would happen.” Given the risk of rape, some women prepare by taking birth control pills. That migrants undertake the journey at all is a measure of their desperation. With a death threat hanging over the twins, the “family decided there was no other option.”

Markham argues that walls won’t keep the desperate away, and she tells a stunning story about one of her students who was loaded into a sack and tossed over a twelve-foot border fence. Build higher walls, she says, and people will dig tunnels or board boats. But tougher enforcement, starting in President Bush’s second term and continuing under President Obama, is one reason that illegal immigration has dropped. (Other reasons include rising opportunity in Mexico and slowing population growth.) Still, Markham is right that many people will come anyway, and a militarized border increases the expense and danger of crossing, as well as the involvement of organized crime. By the time the twins cross the Rio Grande, their father is $14,000 in debt, with interest growing. When the twins fail to send enough money back home, the family loses much of its land.

The boys wander the Texas desert for three days before agents grab them. Raúl expects to be beaten and dumped back in Mexico (he’s already thinking about swimming the Rio Grande to return to Texas). Instead they’re given food and water, held for three days in a windowless room, and transferred to a youth detention center. Adults are usually deported within days of being apprehended, without seeing a judge. But juveniles are entitled to a court hearing, and the 1997 Flores Settlement (no relation) requires their release to a relative when possible. In the twins’ case, that’s their undocumented brother in California, Wilber Jr.

Many on the right see “catch and release”—in this case, sending illegal immigrants to live with an illegal immigrant—as the epitome of weak enforcement. (Trump has called for abolishing migrants’ right to due process altogether.) But family care is much cheaper and more humane than detention, and the government lacks space for everyone. While it’s true that many of those released fail to appear in immigration court, ankle bracelets and other alternatives to detention, while not perfect, are much less expensive than prison and highly effective.

To the twins, Wilber Jr. is a stranger—they haven’t seen him in six years. He is barely surviving on an off-the-books landscaping job, trying to settle down with his girlfriend, and worried about getting deported. The last thing he needs is a pair of teenagers to feed, clothe, and house. They are family, “so of course he’d help them, but damn.”

The “but damn” is important. The migration literature is filled with tributes to the strength of migrant networks, which are indeed a powerful force—personal connections move people around the globe and help them settle. But this safety net also has limits that shape the migrants’ chance for advancement. The apartment is crowded. Strangers move in. Tempers flare. Ernesto accuses Wilber Jr. of stealing and moves out—they are no longer on speaking terms. The conflict is a reminder of how precarious poor immigrants’ lives can be.

Legally, the twins prevail. The victory comes against the odds, after Markham finds them a good low-cost lawyer. (There’s no right to counsel in immigration court.) Their case for asylum would be weak—the government usually finds that people fleeing gang violence are not refugees as defined by international law, so the twins instead seek Special Immigrant Juvenile Status for abused and neglected kids, based on their father’s beatings and inability to protect them from their uncle. (The Trump administration wants to tighten eligibility for the program.) They get an expedited hearing three days before their eighteenth birthday, when their eligibility would expire. A green card—permanent residency—follows.

As the story shifts from survival to assimilation, new challenges arise. The teens are poor and traumatized. Despite the right’s complaints about welfare, they get no government benefits. Raúl and Wilber Jr. are evicted; Raúl nearly winds up homeless. Haunted by the murder he witnessed, Ernesto has night terrors that awaken the house, as if he’s possessed by “evil spirits.” Raúl has flashbacks of the violence he witnessed and can “feel the bomb in his head.” He cuts himself to release the pain and posts pictures of his mutilated arms. Ernesto fears that Raúl may kill himself.

The twins flounder in school, even in a program for non-English speakers. They are chronically late (they work nights) and get in trouble once they arrive. They both get suspended for drinking. Ernesto gets suspended for starting a fight. They get kicked out of summer school for missing class. Ernesto drops out and has a daughter with his fifteen-year-old girlfriend. He can barely support himself, never mind a family.

Given what they’ve suffered, things could be worse. Often absent as students, they are steadfast workers, both as busboys. Ernesto works seven days a week. Raúl “never once missed work”; the physical exertion calms his anxiety. Their capacity for physical labor is a source of pride; they know Americans can’t match it. Indefatigable, uncomplaining, unaccustomed to California wages, they are the low-skilled workers of every employer’s dreams. Their work ethic may be their saving grace.

Still, low-skilled workers have trouble advancing in today’s economy. Even a studio apartment in Oakland costs as much as Ernesto, a new father, earns all month. His predicament is common. About half the Salvadoran adults in the US lack high school educations. A third are unauthorized, and many more have only temporary permission to remain in the States. Mexicans have similar educational backgrounds, and about half are unauthorized. (The estimates are from the Migration Policy Institute.) Together, Mexicans and Central Americans comprise about a third of all immigrants—more than 14 million people. How will they and their descendants fare?

The optimistic scenario is that poor Latinos will more or less follow the course taken by Italian immigrants and their descendants. Like poor Latinos today, the four million Italians who arrived between 1880 and 1920 had peasant roots, prioritized work over school, concentrated on farm and construction jobs, encountered significant discrimination (they were considered nonwhite), and were plagued by organized crime. The Mafia terrorized ethnic communities long before MS-13. Italians advanced more slowly than most immigrant groups at the time, but advanced nonetheless—it’s impossible now to imagine American culture without them. But upward mobility was easier to attain in the mid-twentieth century, when shared prosperity built a great middle class, than it is today, when growth primarily benefits the rich.

A more worrisome prospect is that Latinos encounter the same barriers as blacks, with a significant minority mired in intergenerational poverty. (In that analogy, undocumented status is the new Jim Crow, the legal barrier to mobility.) Overall, the children of immigrants are thriving: they generally outperform the children of natives on measures like education, earnings, and employment. But a subset confronts the same problems as poor minorities with native-born parents—bad schools, dangerous neighborhoods, family breakup, police brutality—and risks the same alienation. The sociologists Alejandro Portes and Rubén G. Rumbaut famously warned that poor immigrants, facing the same challenges as poor Americans, may assimilate downward into a “rainbow underclass.”

The Flores brothers aren’t just poor but socially isolated, barely able to trust even each other. Oakland is much safer than El Salvador, but they still feel surrounded by peril. Each gets assaulted on the street. Markham, a sharp observer of male psychology, notes how they try to look hardened in response, “puffing cigarettes with counterfeit ‘don’t fuck with me’ expressions” to keep threats at bay. Ernesto in particular resents authority. The twins grew up feeling belittled, and living “on the margins of a gentrifying city” reinforces the feeling that “they didn’t, and shouldn’t expect to, belong.” As poor immigrants they have limited opportunities, but they also may have limited ability to capitalize on the opportunities that come their way.

Compared to what the Flores brothers faced in El Salvador, even a hardscrabble life in the States may leave them with the sense that they’ve advanced. (Raúl is certain that life is better; Ernesto is unsure.) But their kids may have higher expectations. The greater danger of downward assimilation comes among the American-born children of poor immigrants. Many view their parents’ dull, dirty jobs with disdain but lack the skills and connections needed to advance. In the worst cases, gang life feeds on this alienation.

It is worrisome how much racial hostility the brothers perceive, even in Oakland, a sanctuary city in the heart of progressive America. Wilber Jr. thinks racism is worse in the US than anywhere in the world. Markham writes that Raúl, watching Univision, wonders why Americans “talked about immigrants like they were some kind of parasite.” Ernesto is busing a table when a customer accidentally knocks a beer from his hand. “Fucking Latino!” the man spits. They nearly trade blows.

One day they hear that a rich guy is running for president. “Do you know he said Mexicans were rapists and criminals?” Raúl asks. “Asshole,” says Ernesto.

The kitchens where they work are “filled with chatter about this guy, his bold racism.” As the campaign wears on, the sense of menace grows. On TV and the Internet, the teens watch “seas of white people chanting ‘Build the wall’ over and over again.” It feels like people are chanting about them. Ernesto sees a video about a homeless Latino in Boston who is beaten and urinated on. “Trump was right,” the alleged assailant said. “All these illegals need to be deported.”

Markham assures the brothers that Trump will lose. But their marginalized status allows them to see some aspects of American life more clearly than their mentor can. “I swear to you—Trump will win,” Ernesto says.

With green cards, the twins are safe from deportation, but Wilber Jr., who has a DUI on his record, is a walking bull’s eye. For him, deportation could be a death sentence. Deportees are desconocido—unknown—and greeted by the gangs in El Salvador with suspicion. “He had two friends who had gone back to El Salvador from the United States and been killed,” Markham writes. “Two.”

The book ends with the election, but the hostility to migrants has only grown since Trump took office. For natives of what Trump called “shithole” countries—nearly 90 percent of immigrants come from the developing world—his presidency is a study in venom. The revocation of DACA made political hostages of several million “Dreamers” brought to the US illegally as kids. (Trump’s move is currently blocked in court.) Trump’s rant about sending Nigerians back to their “huts”—in addition to being unapologetically racist—overlooked the fact that 60 percent have college or graduate degrees.

Even by Trump’s standards, taking children from their parents is extraordinary in its malice. The suffering that families have endured looks less like a byproduct of the policy than the policy itself—cruelty posing as strength. “Womp, womp,” chortled Corey Lewandowski, Trump’s former campaign manager, after being told that a ten-year-old girl with Down syndrome had been taken from her mother. The suffering of disabled children has become a punch line. Though for now Trump has backed down on family separation, the episode only helps distract from the more routine insults to immigrants and incursions on their security and rights.

Trump and his supporters warn that the influx of poor immigrants may lead to the rise of an underclass—an estranged and antagonistic ethnic community—but their animosity only helps to create one. Trump asks for immigrants who “love our country.” The Flores brothers feel the hate some Americans have toward them. While the Trump presidency will pass, this wise book alerts us to how deep the damage may be and how long it may endure.

—July 18, 2018