Read: Trump’s immigration policy gets its moral reckoning

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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