Editor's Note: This article is one of 50 in a series about Trump's first two years as president.

The fact of what was happening dawned before the scope of it did: In the summer of 2017, immigration lawyers and judges began reporting that parents were arriving at immigrant detention centers without their children, who had been placed in custody elsewhere, sometimes thousands of miles away. Not until April of last year, when a New York Times investigation found that some 700 children—many under the age of 4—had been separated from their parents after crossing the southern border illegally with them in the preceding six months, did the extent of the program become clear.

Though Donald Trump’s administration has intermittently denied that family separation was ever its policy, the litany of horrors associated with the policy lengthens. Toddlers screaming as they’re wrested from their parents’ arms. Children sleeping on the bare floor of cages. Parents getting deported to their home countries while their children remain in custody here. Children falling ill in custody. Border Patrol losing track of where certain children have gone. (When a federal judge ordered that children be reunited with their families immediately, it quickly became evident that border agencies had little idea how to do so.)

Separating families was not a rare and unintended consequence of a policy but part of the point of it. Not long after Trump took office, senior officials in the Department of Homeland Security began saying that the administration was considering separating children from their parents as a deterrent to illegal immigration. Is that true? John Kelly, then serving as the head of DHS, was asked in early 2017. “Yes I'm considering” that, Kelly said. “I am considering exactly that.” (Kelly would later blame the policy on departed Attorney General Jeff Sessions’s “zero tolerance” policy toward illegal immigration.)

It is an axiom of moral life among civilized humans that to separate young children from their parents is an offense against not just nature but society, one of the building blocks of which—as the Republican Party, in particular, has long been at pains to emphasize—is the family. Forcibly yanking children from their parents is of a piece with some of the darkest moments of American history: the internment of Japanese Americans; the forcible separation of American Indian children into special boarding schools; slavery.

Wanting to clamp down on illegal immigration is a reasonable policy position; the relative expansiveness with which this country grants asylum is a subject of legitimate debate. What is new is the callousness of the Trump administration’s approach, which is in keeping with what seems like an odd deficiency of human sympathy on the part of the president himself. In December, when two children who had not been separated from their parents—Jakelin Caal Maquin, age 7, and Felipe Gómez Alonzo, age 8—died in U.S. custody, the president’s first response was not an expression of condolence or concern but rather a statement blaming others and calling for a border wall: “Any deaths of children or others at the border are strictly the fault of the Democrats and their pathetic immigration policies,” he tweeted.  

Even for those children who survive the border-crossing ordeal, the damage will be lasting: Research on the toxic and enduring effects of early-childhood separation from primary caregivers is abundant. What the effect of this progressive coarsening of our moral sensibilities will be is yet to determined.

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