From the op-ed:
How could deporting people make local labor markets worse? Jobs are not a fixed commodity that get parceled out to whoever is in the neighborhood; that’s a common fallacy. The people deported to Mexico in the Depression weren’t just workers, they were also consumers -- their demand supported local businesses. When the government stepped in and removed them, local businesses naturally suffered.
That wasn’t the last time the U.S. tried to support native-born workers by keeping out Mexican laborers. In 1965, the U.S. ended a program that allowed Mexican farm workers, called braceros, into the country on a temporary basis. The idea was to raise wages and provide jobs for native-born agricultural laborers.
But a recent study by economists Michael Clemens, Ethan Lewis, and Hannah Postel finds no evidence that the policy worked as designed. Wages didn’t rise in the sectors where workers were excluded, nor did more native-born Americans take the jobs. Many farmers either switched to crops that required less manpower to pick, or invested in more automation. Sometimes they simply grew less, which probably resulted in higher food prices for American consumers.
So the benefit of mass deportation to the native-born is low or even negative. Crops will rot in the field, local businesses in cities across the country will lose customers and landlords will lose tenants. These costs will cancel out whatever benefits native-born Americans see from having low-paid, low-skill jobs suddenly open to them. Taxpayers might save a little money from not paying for unauthorized immigrants’ kids to go to school, but that’s about it. Meanwhile, the U.S. government will become a more repressive, more intrusive entity, eroding the freedoms that Americans have traditionally prided themselves on.