Restricting immigration to appease domestic political grievances is likely to backfire—again.

Ahead of the U.S. presidential election this November, many U.S. voters—mostly Republicans and independents—have listed immigration among their top concerns. Last year, authorities registered a record nearly 2.5 million encounters with migrants at the U.S.-Mexico border. Republicans and their presumptive nominee, former President Donald Trump, argue that the United States is experiencing an immigration crisis that is the result of President Joe Biden’s poor management of the issue.

If reelected, Trump has promised to crack down on immigration and launch a mass deportation campaign resembling then-President Dwight D. Eisenhower’s infamous 1954 “Operation Wetback,” the goal of which was to root out undocumented Mexican laborers (although the program indiscriminately expelled many naturalized U.S. citizens as well). Meanwhile, Biden has significantly expanded restrictions on asylum and promoted bipartisan legislation that would grant him greater authority to oversee migration at the border. He has criticized Republicans for their lack of support for the measure in the Senate; many decried it as a “sham.”

Today’s U.S. immigration debate—with politicians on both sides of the aisle promoting restrictive policies and contesting who should be allowed into the country—mirrors that of a century ago, when President Calvin Coolidge signed into law the Immigration Act of 1924.

Months earlier, Coolidge had remarked in his State of the Union address that “America must be kept American.” At the time of its passage, the 1924 law became the strictest immigration policy enacted in U.S. history, significantly reducing the country’s foreign-born population and fundamentally altering its demographics for the next four decades. Lawmakers repealed the act in 1965, concluding that it was both unjust and detrimental to the country’s economic potential.

Now, 100 years later, Washington seems poised to make the same mistake—pursuing restrictive immigration policies based on domestic political grievances that are likely to backfire by dampening U.S. economic growth.

The 1924 law reflected growing xenophobia and racism, concerns over rising economic inequality, and a fear of the spread of communism following World War I. “Let us shut the door and assimilate what we have,” South Carolina Sen. Ellison DuRant Smith said during a congressional debate over the act, “and let us breed pure American citizens.”

Such sentiment was widespread at the time. Growing numbers of Eastern and Southern Europeans had been migrating to the United States, and by 1920, foreign-born people accounted for more than 13 percent of the U.S. population. The nativist-inspired 1924 act introduced a nationality-based quota system that limited future annual immigration to 2 percent of the total number of people of certain nationalities who were already living in the United States and capped total immigration at 150,000 people annually. (It did not set quotas for immigrants from the Western Hemisphere.)

Because the act was based on population records from the 1890 census, it disproportionately favored immigrants from Northern and Western Europe compared to their Eastern and Southern European counterparts. It also completely excluded immigrants from Asia, including those who had previously been allowed to immigrate to the United States. (The 1882 Chinese Exclusion Act was still in effect at the time and would not be repealed until 1943.)