Trump and Biden blame each other for illegal immigration. But Congress created it.

Presidential candidates Joe Biden and Donald Trump have agreed to debate, and there is no doubt immigration will feature prominently. We already know what they’ll say: Trump will insist Biden opened the floodgates, while Biden will blame Trump for torpedoing a bill to cut entries. They have taken the immigration debate back 100 years – the last time both parties wanted to slash immigration.

In May 1924, President Calvin Coolidge signed the National Origins Quota Act, which included the first permanent cap on legal immigration. This law laid the groundwork for a century of legal immigration restrictions. The fundamental elements of America’s system came from this law: a low overall cap and country-by-country limits, with preferences for relatives of U.S. citizens.

This law has walled off the legal immigration system to most people who would like to come, leading to massive amounts of chaotic illegal immigration.

In new research published by the Cato Institute, I show that the National Origins Quota Act resulted in immediate and lasting devastation to the legal immigration system. From 1888 to 1921, 98% of applicants for permanent residence were approved. Every year since 1924, a minority has been approved.

By the 1930s, more than 90% were blocked annually, including Jews fleeing the Holocaust.

Of 35 million immigration applications, only 3% will likely pass

Even though Congress slowly began to open the system back up after World War II, its loosening of restrictions never undid the basic framework of the 1924 law. By 1995, more than 10 million requests were submitted. This year, the number has hit an unprecedented 35 million – only 3% of which will likely be approved, matching the lowest rate on record.

It's not just that the United States admits a low percentage of applicants. The backlog is also so large that millions of people – likely a majority of pending applicants – will die before they can immigrate legally.

There is no hope just around the corner. Even most of the highest-skilled applicants face the prospect of waiting more than a century for a green card.

What migrant surge? No, America is not seeing an unprecedented surge in immigration.

America’s century of restrictions didn’t just fail: It backfired.

When most people can’t come and live here legally, many give up and come illegally. As a result, the United States has had to deal with decades of illegal immigration.

Border Patrol has made nearly 60 million arrests from 1925 to 2024, including about 20 years with more than a million or more arrests.

Illegal immigration results when legal immigration is too difficult

Illegal immigration was a choice, and in the 1920s, everyone knew why it was happening. Congress had just passed a law to prohibit most immigration. Commentators analogized it to alcohol Prohibition, labeling human smuggling networks as “bootlegging in people.”

There was no doubt that Congress had created the problem or that it could end it the way that it did with alcohol bootlegging: re-legalize immigration.

Biden has the right border plan, but arbitrary caps have actually blocked legal migration

Today, most people do not understand how difficult it is to immigrate legally. Only 41% of Americans believe illegal immigration happens because legal immigration is too difficult, according to Cato’s polling.

In addition, 80% say immigration should take five years or less, yet we are still processing some family-sponsored applicants who applied before 9/11.

Americans see undocumented immigrants without jobs in homeless shelters, and they have decided that we have too many immigrants. But immigrants are ending up in shelters because we don’t let them line up jobs and housing in advance of them coming, and they are prohibited from working legally for many months after they are released at the border.

Immigration reduces US deficits and increases our GDP

Despite all these issues, the Congressional Budget Office recently found that recent immigration will reduce deficits by $1 trillion and increase the size of the economy by $7 trillion.

Immigration is working – or, more accurately, immigrants are working. It’s our legal system that’s broken.

Indeed, we don’t have too many immigrants. We have too few. The United States has nearly 8.5 million open jobs and a record period of low unemployment rates.

Our labor force would be declining without immigration at a time when we are tens of millions of workers short to pay into retirement systems and care for our elderly population.

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While some people claim that America’s policy is already “the most generous in the world,” the United States ranks in the bottom third of wealthy countries for its foreign-born share of the population. We let in more immigrants than any other country, but America is a huge country. We let in far fewer on a per-capita basis.

For America to reach the foreign-born share of Canada, we’d need to let in 35 million immigrants tomorrow. Even admitting that many over five years and increasing immigration fivefold wouldn’t catch the U.S. foreign-born share up to our neighbor to the north.

The United States has plenty of room to grow. The only question is whether our political institutions will allow it.

A century of immigration restrictions hasn’t worked for America. It has made America a smaller and less prosperous country, but it hasn’t stopped immigration. It has made it more chaotic, disorderly and illegal.

America should return to its pre-1924 traditions. If you’re willing to come legally, work and contribute, America should welcome you, just like it welcomed generations of immigrants a century ago.

David J. Bier is the director of immigration studies at the Cato Institute.

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This article originally appeared on USA TODAY: Immigration restrictions don't work for US. Reverse outdated quota law