Democratic governments have shown over and over that they have no answer for this anxiety, even as the stakes, in Europe and globally, continue mounting.

Facts Cannot Compete With Feelings

The economist Michael Clemens has called immigration a “trillion-dollar bill lying on the sidewalk”: a tremendous increase in wealth waiting to be seized by any country that is attractive to immigrants and willing to welcome them. Loosening restrictions on global labor flows, he argues, would offer a bigger boost to global economies than would dropping all restrictions on trade and capital.

But evidence does not vote — people do. And it turns out that the gains of immigration often feel elusive, whereas the costs can be perceived as heavier than they really are.

A poll released June 20 by Ipsos/MORI showed that 47 percent of voters planning to support Brexit said immigration had been bad for Britain’s economy. Never mind that a study by Britain’s National Institute of Economic and Social Research found that immigration had increased the country’s gross domestic product and had lowered the cost of government services like health care and pensions, which in turn helped reduce taxes.

To be sure, just because immigration is a net positive for the country as a whole does not mean that it benefits all of its people. The geographic breakdown of Thursday’s vote showed that the regions where the Leave campaign fared the best were areas that tend to have few immigrants but also lower wages, according to analysis conducted by Torsten Bell, the director of the Resolution Foundation, a British think tank.

This suggests that economic anxiety might be expressed as anti-immigration sentiment even by Britons who have not lost jobs to foreigners.

“You tend to see anti-immigrant sentiment in areas hit by changing economic circumstances or global crises,” said Alexandra Cirone, a fellow at the London School of Economics. “Framing this globalization problem as immigration can also tug on the heartstrings of potential voters, regardless of the actual facts.”