The old standby explanation of populism is that it is a predictable response to economic oppression. Thus, the socialist pundit John Judis argues in 2016’s The Populist Explosion: How the Great Recession Transformed American and European Politics that populism rose in response to “the skewed distribution of jobs and income that neoliberal economics had created over the prior decades.”

Yet populists have surged in popularity or come to power in countries with very dissimilar economic conditions, including some with low unemployment and relatively high economic growth. Nor is the rise of populism a matter of age, with older people supporting right‐​wing nationalist populists and younger people supporting liberal cosmopolitanism: Plenty of young people have been voting for populist parties and candidates. Nor is the populist vote explained robustly by income levels.

The British political scientists Roger Eatwell and Matthew Goodwin point out in their 2018 book National Populism: The Revolt Against Liberal Democracy (Pelican) that a common driver in “national populism” is not falling wages but “relative deprivation—a sense that the wider group, whether white Americans or native Brits, is being left behind relative to others in society, while culturally liberal politicians, media and celebrities devote far more attention and status to immigrants, ethnic minorities and other newcomers.” Rapid change in the status of groups, notably through immigration, causes many people to experience relative downward mobility and to feel that the status of their group is threatened. When Britain voted to withdraw from the European Union, Eatwell and Goodwin write, polling data showed Remainers “talking endlessly about economic risks while Leavers were chiefly concerned about perceived threats to their identity and national groups.” (Brexit is a complex question, of course, and some classical liberals supported it because they feared an unaccountable E.U. bureaucracy. But the movement for Brexit was driven far more by populist concerns than by liberal ones.)

In the U.S., a deciding factor in Trump’s victory was the estimated 9 percent of voters who cast ballots for Obama in 2012 and then switched to Trump, according to survey data analyzed by George Washington University political scientist John Sides. Among white Obama voters who had not been to college, the share who later voted for Trump was a whopping 22 percent. As that past support for Obama suggests, their votes for Trump can’t be reduced to a simple story of racial backlash. Nor was it a simple matter of economics: For the most part, those voters’ incomes and living standards are higher than those of their parents.

But a common motivation for their support for Trump seems to be insecurity about their social status. A 2016 Brookings Institution survey showed that 66 percent of non‐​college‐​schooled American whites “agree that discrimination against whites is as big a problem today as discrimination against blacks and other minorities.” Anxiety about status—in this case a perception of an inversion of the status quo—seems to be a major factor, certainly much bigger than ideological racism. As political scientist Karen Stenner argued based on extensive data in her 2005 book The Authoritarian Dynamic , threats to “collective rather than individual conditions” trigger authoritarian “groupiness,” i.e., populism.

Here’s where classical liberals need to do some serious thinking. A mainstay of arguments for free markets is that when people’s incomes rise at different rates, the important thing is that they’re all rising. Even most left‐​wing egalitarians accept some inequality, as long as it’s necessary for the poor to become less poor. The philosopher John Rawls argued in A Theory of Justice, for instance, that inequalities can be just if they are to the “greatest benefit of the least advantaged,” because then, even the least well off could not complain. But human beings are concerned about more than how well they’re doing relative to how well they did in the past. They also care about how well they’re doing compared to others. They care about hierarchies and social status.

Relative status is quite different from absolute well‐​being. Libertarians have for many years celebrated the rise in status of women, racial minorities, immigrants, openly gay people, and others who had for very long periods of time suffered from low social status. Well, when it comes to relative social status, if some rose, others had to fall. And who perceived themselves as falling? White men without college degrees.

It isn’t just onetime outsiders rising in comparative status. As Charles Murray lays out in his 2012 book Coming Apart: The State of White America, 1960–2010 , a decline in our collective emphasis on certain traditional virtues—hard work, marriage, and the like—has opened a gulf between college‐​schooled elites and high‐​schooled nonelites. The resentment felt by one side of the divide is, unfortunately, often matched by the arrogance and condescension shown by the other, which merely accentuates the resentment.

Similar divisions are happening in other countries as well, and they seem to be a major driver of populist sentiment. Pew Research Center surveys conducted in 2017 in 15 countries identified ethnocentrism and perceptions of national decline as characteristic of populist voters. In Germany, for example, 44 percent of the populist Alternative for Germany (AfD) party’s supporters say that life is worse than it was 50 years ago for people like them, compared to only 16 percent of other Germans. While data vary across countries and, as Berlin pointed out in 1967, no one factor can explain all populist movements, such fears of national decline and group status are common, especially in Europe and the U.S. The most important driver in Europe and the U.S. seems to be immigration and what Eatwell and Goodwin in National Populism call “hyper ethnic change”—that is, rapid change in the ethnic mix of a society, with multiple ethnicities joining the social order. (Some Americans have experienced feelings of dislocation and threat to their place in society upon seeing that their old Piggly Wiggly store has been replaced by a mercado with Mexican flags. It’s not the experience of ethnic pluralism that seems to be the problem but the fear that other ethnicities will eventually displace them.)

The percentage of U.S. residents who were foreign‐​born reached 13.7 percent in 2017, the highest percentage since 1910, when it was 14.7 percent. Moreover, since the Immigration and Naturalization Act of 1965, which abolished national quotas and favored family reunions, higher percentages of immigrants have been coming from Asia, Africa, Central America, and the Middle East, accentuating ethnic differences with the native‐​born population.

The Alternative for Germany, which started as a movement against the euro and has morphed into a populist anti‐​immigrant party, has drawn increasing support from less‐​schooled voters from the former states of East Germany. Such voters perceive their status as having fallen in recent decades, and they fear immigration far more than do more‐​schooled voters and those in the Western part of the country, which has seen far more immigration. In fact, the AfD support was strongest in those regions of the East that had seen the least population growth due to migration; people in those places feel that they are being left behind, and they blame immigrants, whom they see more on television than in their neighborhoods.

Similar analyses can be applied to Britain, France, Sweden, and other democracies that have seen surges of populism.

Hyper ethnic change is profoundly unsettling to many people, and it is helping to drive populist political responses. One can dismiss such reactions as irrational or small‐​minded, but many people feel them nonetheless. Moreover, many people are not satisfied with improvements in their conditions if they perceive others—especially outsiders—as doing even better. Envy and resentment have long been drivers of anti‐​libertarian movements, and they seem to be back in a big way. The problem is exacerbated by the increase of welfare‐​state transfer payments and benefits, which outsiders are believed to exploit or threaten.

I fear that we may be entering an age of authoritarian “groupiness” and that the consequences will be terrible for freedom and prosperity. Not to put too fine a point on it, but the rise of far‐​right and far‐​left authoritarian populist movements today is more than a little reminiscent of Europe in the 1930s.