When you think about the current political fight over immigration enforcement, start with this: There are millions of people, at least 15 million and perhaps as many as 20 million, who are in the United States illegally. Millions of them are new arrivals with no claim to stay in the U.S., having arrived in the mass border incursion of the Biden years. Many should be deported. But in our system, it is very hard to deport millions of people. It is easier to get them to deport themselves.

In the 2020 election, Democratic primary candidates vied with each other over who could offer the most open-borders policy. The winner, Joe Biden, went on to the White House and presided over the influx of millions of illegal border crossers. The Biden border catastrophe was one reason Donald Trump won in 2024. And now, President Trump is making good on his campaign promise to ramp up deportations.

It is controversial, to say the least. And it has fired up a debate over whether “illegally” really means “illegally,” or whether those who crossed into the United States in defiance of its laws should be allowed to stay with few, if any, consequences. In short, should the United States enforce its immigration law, or not?

It’s not clear precisely how much Biden increased the number of people who are in the country illegally. On the low end, there’s this, from Pew Research: “The number of unauthorized immigrants in the United States reached an all-time high of 14 million in 2023 after two consecutive years of record growth. … The increase of 3.5 million in two years is the biggest on record.” Of course, in 2023, there was still nearly two more years of the border rush to go, so the actual number is definitely higher. On the high end, there could be 20 million people in the country illegally.

During the campaign, while Trump repeatedly promised “mass deportations,” he focused on deporting illegal immigrants who had committed serious crimes beyond illegally entering the United States — the so-called “worst first” strategy. In office, the Trump administration has certainly done a lot of that.

But the Trump team is also staging high-profile enforcement operations at worksites likely to have a lot of illegal immigrant workers. Some of them have additional criminal records, but others do not. What is the thinking behind that? It is that high-profile immigration actions have effects far beyond any specific business targeted on any specific day.

During the transition, Art Arthur, a former immigration judge who is now with the Center for Immigration Studies, explained the work involved in deporting even a single person. That person would be placed in removal proceedings before an immigration judge. “Some of them have made asylum claims,” Arthur said. “Some didn’t make any claim at all. Some of them may have come many years ago, and they’ve been sitting on the docket for decades.” Arthur said the U.S. has the resources to remove about 400,000 people per year — maybe 600,000 if officials are given more money and staff.

But last month came reports that 1.6 million people who were in the U.S. illegally left the country between January and July. “This is likely due to increased out-migration in response to stepped-up enforcement,” noted CIS. The administration’s widely covered immigration actions gave illegal immigrants the reasonable fear that being in the United States illegally could one day become a major problem for them. So many of them left — a process that likely continues today. It turns out the “mass deportations” that Trump promised in the 2024 campaign are happening — except they are in fact mass self-deportations.

If the Biden years proved anything, it is that there have to be consequences for entering the United States illegally. If there are no consequences, the flow of illegal crossers will get bigger and bigger and bigger. As for the disruption in the lives of those illegal immigrants who choose to leave, first, they did enter the U.S. illegally, and second, many of those targeted in the Trump enforcement haven’t been in the country for very long. Pew noted that “a record number of unauthorized immigrants have been in the U.S. for a relatively short time due to the rapid growth in the overall unauthorized population since 2021.” Those leaving because of the raids are likely to include many who have the fewest ties to the United States.

Meanwhile, the political battle over Trump’s policy rages on. Many Democrats have pledged to resist Trump’s enforcement of immigration law. Some have tried to blur the distinction between legal and illegal immigration, as if all have the right to stay in the United States, in hopes of turning public opinion against Trump’s actions. But Trump has the law on his side.

This content originally appeared on the Washington Examiner at washingtonexaminer.com/daily-memo/3798172/what-the-immigration-raids-are-about/.