A victory for Democrats this midterms, President Donald Trump warned before the election, is a victory for a terrible, dangerous idea: open borders.

Trump is entirely making this up, to be clear, but he’s hammered this point repeatedly. “The Democrat platform is a 2018 socialism, open borders edict,” he declared at a rally in Cleveland the night before the election. In October, he informed a Kansas crowd that “Every single Democrat in the U.S. Senate has signed up for the open borders, and it’s a bill, it’s called the ‘open borders bill.’” (No, they haven’t, and there’s no such bill.) Democrats, he tweeted in June, “want Open Borders and Unlimited Crime.” (While “Unlimited Crime” is a cool band name, it’s not a real proposal.)

The US does not have anything resembling open borders, and no major politician in the US wants to have open borders. But Fabio Rojas does want open borders, and on the latest episode of the Future Perfect podcast, he tells us why.

Rojas, a sociology professor at Indiana University Bloomington, is part of a small but growing movement of libertarians and leftists who are questioning the need for any restrictions on entering the United States.

Immigration to the US, open borders advocates argue, raises most native-born Americans’ incomes, promotes innovation by increasing our pool of skilled entrepreneurs and inventors, and hasn’t led to major problems with assimilation. “Migrants create jobs because they have to eat, which means they have to buy stuff from the supermarket. They have to drive a car, which means they have to go to the gas station,” Rojas explains. “So in the same way that a person from Indiana doesn’t steal a job from a native of Chicago, a person from Mexico doesn’t steal a job from a person in California.”

To most people engaged in practical politics, this all might sound absurd. The Trump administration is locking up migrant children, whipping up a racist panic against a “caravan” of aspiring immigrants, and threatening to end birthright citizenship. Doing anything remotely positive for immigrants in that environment is hard; open borders sounds downright fantastical.

Leon Fresco, an immigration attorney who was the primary drafter of the 2013 “Gang of Eight” immigration bill and served as deputy assistant attorney general for the Office of Immigration Litigation under President Obama, has spent much of the Trump years trying to get a very tiny change to immigration law: a tweak to make it easier for Chinese and Indian immigrants to get green cards (they are currently limited by arbitrary per-country caps). The idea has massive bipartisan support, with senators from Tom Cotton on the right to Kamala Harris on the left signing on and 329 co-sponsors in the House (more than three-quarters of the House’s members).

But even that has been a struggle! “People have asked us to, I don’t know, show us that you have a thousand members in our district that care about this!” Fresco recalls. “And so we’d have to come up with a rally in, you know, a week.” When we asked Fresco what he’d say if we asked him to strategize for an open borders bill, he replied, “The very simple answer is we can’t get that accomplished.”

Rojas, whose sociological work studies how once-fringe movements (like Black Power or the antiwar movement in the early 2000s) can become mainstream, is more optimistic. “A couple of hundred years ago, if you said that black people and white people were equal in the eyes of God, people would have been horrified. They would have said, ‘No, no, blacks and whites are different.’ But you just slowly make the argument,” he says. “We have to communicate with people and say: America is a great country when it’s a country of open doors.”

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