“It’s not a desirable situation to have children separated from their parents,” Alex Azar, the Secretary of Health and Human Services, told a session of the Senate Finance Committee on Tuesday, when Democratic members pressed him to explain what, if anything, was being done to locate the more than two thousand migrant children who had effectively disappeared in H.H.S. custody, after being taken from their families under President Trump’s zero-tolerance border policy. “To be upfront,” Azar said, “if the parents didn’t bring them across illegally, this would never happen.” In fact, the President had already all but acknowledged that he was the reason that this had happened. Last week, in an attempt to mollify intensifying public outrage, without offering migrants any great relief, Trump signed an executive order that revised the border protocol, halting family separation in favor of keeping children in indefinite detention with their family members. This hardly settled the matter, since the indefinite detention of children is illegal. What’s more, the executive order made no provision for locating the children who had already been taken and reconnecting them with their families. The Senate Democrats wanted to know when those children would be produced. Azar stonewalled. “There is no reason why any parent would not know where their child is located,” Azar said, explaining that there was “a portal” in his office that put all such information at his fingertips. “I could, at the stroke of keystrokes—within seconds—could find any child within our care for any parent.”

Before the day was out, a federal judge in San Diego had called Azar’s bluff, ordering the Administration to reunite the children with their parents within thirty days, or within fourteen days in the case of children under the age of five. The judge, Dana M. Sabraw, who was appointed by President George W. Bush, found that Trump’s family-separation policy had been “implemented without any effective system or procedure for (1) tracking the children after they were separated from their parents, (2) enabling communication between the parents and their children after separation, and (3) reuniting the parents and children.”

“This is a startling reality," Judge Sabraw continued. “The government readily keeps track of personal property of detainees in criminal and immigration proceedings. Money, important documents, and automobiles, to name a few, are routinely catalogued, stored, tracked and produced upon a detainees’ release, at all levels—state and federal, citizen and alien. Yet, the government has no system in place to keep track of, provide effective communication with, and promptly produce alien children.”

The Trump Administration had made family separation a practice even before Attorney General Jeff Sessions declared the zero-tolerance policy, in April. The class-action suit that prompted Sabraw’s order was brought by the American Civil Liberties Union in February, on behalf of parents who had been held apart from their children for many months without contact. And they were the fortunate ones: those parents were ultimately able to find their sons and daughters. In the absence of a family-reunification plan, Sabraw noted, “Some parents were deported at separate times and from different locations than their children.” The judge described the thousands of remaining children covered by his order as “essentially orphaned” by the President’s policy.

Reading that phrase brought to mind a story that a Rwandan bank-security specialist, named Norbert, told me in Kigali a few years ago, about losing his little brother in eastern Congo in 1996. Norbert was twelve at the time; his brother had just turned ten. They had crossed into Congo with their parents in 1994, after the genocide in Rwanda, and were living in refugee camps outside the border city of Bukavu. Then the Rwandan Army and an alliance of local rebel groups broke up the camps, driving hundreds of thousands of people deeper into Congo. “We fled into the forest,” Norbert said. “It’s in that forest that many people were lost. And it was in that forest that we lost our little brother.”

They had been walking for about two weeks, moving only under the cover of darkness. “There was shooting,” Norbert said. “People ran in all directions. It was horrible. He got separated.” Another family also lost a son that night. Later, friends found that boy and reunited him with his family, but he didn’t know what had become of Norbert’s brother. Nobody did.

The family wandered in the forest for six more months before they found their way back to Rwanda. Five years passed, and Norbert’s parents had another child, a girl. One day, some people appeared at the door and introduced themselves as field officers of the International Committee of the Red Cross. They showed Norbert’s mother a photograph of a young man and asked if she could identify him—and there he was, her lost son.

The I.C.R.C. had found him a thousand miles away, in a village in Congo-Brazzaville—the other Congo, the Republic of Congo. He was one of many unaccompanied Rwandan children who had fetched up there. A local family had taken him in. They regarded him, as he regarded himself, as essentially orphaned. It had never occurred to him that his own family might still exist as anything but a memory; and even that memory was uncertain. When the I.C.R.C. officers there asked him his parents’ and his siblings’ names, and where they were from in Rwanda, he drew a blank. It was only with some effort that he exhumed those long-buried sounds. A few months later, he was home.

“Can you imagine?” Norbert said. “That was the happiest moment in my life.” He experienced his brother’s reappearance less as a case of lost and found than as a resurrection. “It was a miracle,” he said.

Norbert hadn’t known that, for a century, the I.C.R.C. has devoted extraordinary resources to tracing people, particularly children, who have been displaced and dispersed by conflict and its attendant catastrophes, with the aim of reuniting families. He did not know that I.C.R.C. teams maintain extensive databases, and are constantly cross-referencing information, and facilitating communications between the far-flung and the trapped—refugees and incarcerated people. He’d never heard of Red Cross messages, which allow, say, a child and parent who have become separated, to leave word for each other when they don’t know where the other person is or even whether he or she is alive. As Norbert came to understand the scale and the determined relentlessness of the I.C.R.C.’s project, he still reckoned his brother’s return uncanny. The system had worked. “Can you imagine?” he said again.

A Crisis at the Border More coverage of the Trump Administration’s immigration policy from The New Yorker.

Judge Sabraw, in ordering the U.S. government to reunify migrant families without delay, wrote that the facts of Trump’s policy “portray reactive governance—responses to address a chaotic circumstance of the Government’s own making. They belie measured and ordered governance, which is central to the concept of due process enshrined in our Constitution.” The separation of migrant families, he argued, met all the legal standards for issuing such an immediate order: it was “so egregious, so outrageous, that it may fairly be said to shock the contemporary conscience”; it was so “brutal” and “offensive” that it does “not comport with traditional ideas of fair play and decency”; and its victims were “likely to suffer irreparable harm in the absence of preliminary relief.”

Just two days earlier, Trump had made clear what he thinks of due process for migrants, when he tweeted, “We cannot allow all of these people to invade our Country. When somebody comes in, we must immediately, with no Judges or Court Cases, bring them back from where they came.” This is how Trump asserts power and, in an election year, how he pursues it: by inflicting trauma and inciting fear. There have been numerous reports that hundreds of migrant children who were separated from their families may never be found, or may never find their families. According to the Washington Post, “attorneys and former U.S. officials have begun speaking about the possibility of ‘permanent separations.’ ”

Yet, if a child like Norbert’s brother—a child so truly lost that he could no longer imagine ever seeing his family, and his family could no longer imagine ever seeing him—can be found and delivered to his family’s doorstep, then the Trump Administration can fulfill Sabraw’s order. If it fails to meet his deadlines, there can be no excuse.