A view of inside U.S. Customs and Border Protection (CBP) detention facility shows detainees inside fenced areas at Rio Grande Valley Centralized Processing Center in Rio Grande City, Texas, on June 17, 2018.Reuters / CBP

“The man the city sets up in authority must be obeyed in small things and just but also in their opposites,” declares the tyrannical king in the ancient Greek tragedy Antigone. The plan to which he demands obedience calls for separating a brother and a sister across the city’s border—an act terrible in its cruelty but, he argues, necessary for security. The king wants to reestablish order in the city, and he is using the brother’s fate as a deterrent.

In the family separation described by Sophocles, the brother is not just exiled but dead; the king, Creon, has left his body to rot outside the city walls without a burial. The Trump administration has not engineered anything quite this cruel. But when it justifies pulling migrant parents away from their children at the U.S. border, it is speaking Creon’s language.

The New York Times reports that the administration began systematically separating parents from children at the border last month, reasoning that a policy this cruel would deter other would-be migrants from making the trip north. Almost 2,000 children were removed from their parents between April 18 and May 31. In the eight months prior, 700 children were separated.

“It was a simple decision by the administration to have a zero-tolerance policy for illegal entry, period,” said White House aide Stephen Miller, who engineered the policy. “The message is that no one is exempt from immigration law.” “Orderly and lawful processes are good in themselves,” Attorney General Jeff Sessions argued. “It’s a moral policy to follow and enforce the law,” White House Press Secretary Sarah Sanders told reporters. Former Trump adviser Steve Bannon went a step further: “The morality is the law,” he said when confronted with a photograph of a crying child.

This is Creon’s position: The law is the law and must be followed, and it is good to follow it because it is the law. But Creon ends the play a husk, destroyed by the cruelty of his own arguments. And reading the 2,500-year-old text today is a reminder both of the visceral wrongness of what is happening at the border and of the emptiness of the administration’s arguments about law enforcement.

Antigone is a simple story. Polynices, the brother of the play’s heroine, is killed while leading an attack on the city of Thebes during a civil war. Creon, who has taken power, orders his corpse left outside the city walls as a warning. Antigone nevertheless insists on her religious obligation to bury her brother. Creon himself is convinced of his own error only after he orders Antigone killed and his own son—Antigone’s fiancé—kills himself in protest.

The play is about law, authority, and defiance. It is also about borders. In banishing Polynices’s body, Creon is reaffirming the distinction between whom he wants in his city and whom he doesn’t, defining the boundaries of his community. He refuses to allow Polynices back into Thebes, even in death, and refuses Antigone passage out of Thebes to bury her brother. When she sneaks out in the night and does so anyway, Creon is furious. He demands her execution. The choice is either order or disorder, he reasons, and the danger of disorder is so great that the cruelty of order is justified.

Like Creon, the White House uses the specter of chaos to justify its “zero tolerance” policy. “There is nothing worse than disobedience to authority,” Creon says, explaining why Antigone’s transgression must be punished with death. “It destroys cities, it demolishes homes.” Similarly, Miller told the Times, “No nation can have the policy that whole classes of people are immune from immigration law or enforcement.”

The anxiety of the border as the focal point of lawlessness has been a theme throughout Trump’s presidency: In October 2017, for example, Sessions linked what he described as an absence of immigration enforcement with a wider breakdown in “respect for the rule of law.” And on Monday, the president declared: “A county without borders is not a country at all. People coming into the country are bringing death and destruction.”

One way to read Antigone is as a total repudiation of Creon’s vision of authority. The other—adopted by, among others, the philosopher Hegel—is that Antigone and Creon are both partly right. Law is not the single, rigid thing both Creon and Antigone imagine it to be. Law, instead, is a network of sometimes-conflicting obligations, tempered by choice and mercy. It can require both the maintenance of order and the burial of the dead.

But family separation is the result of immigration enforcement only if you take the harshest view of the law possible. There is no legal requirement as such that migrant families be separated. Rather, the Trump administration is pushing to refer 100 percent of adults apprehended crossing the border illegally for criminal prosecution—a change from previous administrations. The children are then removed as a result of their parents’ detention before trial.

In the universe of criminal law, crossing the border illegally is a relatively minor infraction, punishable with only a short time in jail. And as the law professor Ilya Somin writes, the federal statute criminalizing such crossings does not mandate criminal penalties: It also allows for civil penalties, which don’t require jailing parents and therefore allow families to remain together. This is not the binary described by Secretary of Homeland Security Kirstjen Nielsen, who suggested at Monday’s press briefing that the administration’s options are either separating families or not enforcing the law at all. What’s more, no crimes committed in the United States are prosecuted 100 percent of the time. To quote Supreme Court Justice Robert Jackson: “No local police force can strictly enforce the traffic laws, or it would arrest half the driving population on any given morning.”

The government instead relies on what’s known as prosecutorial discretion, choosing to pursue only the cases in which, as Jackson put it, “the offense is the most flagrant, the public harm the greatest, and the proof the most certain.” For this reason, previous administrations chose not to prosecute every single illegal border crossing—as a matter both of limited resources and of basic humanity. And so the Trump administration’s “zero tolerance” is not a choice between order and disorder but a decision between mercy and cruelty.

The images of crying children separated from their parents and hunched behind chain-link walls are so gut-wrenching that the slogan of those campaigning against the practice has a pure, almost religious simplicity: “Families belong together.”

Among the many lessons of Antigone is that law enforced too harshly does become cruelty, and that Creon’s law is not good just because it is the law. It would be foolish to expect self-reflection from President Trump. But at the end of the play, his wife and son dead, Creon finally recognizes the error in his brittle understanding of his authority. “It was my hard killing mind,” he cries in the poet Anne Carson’s translation. “It was my deadly goings wrong … this sacrilege that I called public policy.”

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