II. The Move to Cities

Communities work well when the population that comprises them remains relatively stable and small. These are the conditions in which people know one another well enough to develop and share a common set of norms and social expectations. In especially large and heterogeneous groups, norms are difficult to police through informal sanctions and the members of these groups tend to develop different standards of behavior. When large groups with different standards live in the same place and there is frequent migration in and out of an area, coordination becomes difficult and trust declines.Footnote ⁷

Many people are shocked when they move to a large city from a small town. People are less polite, customs change, trust declines, and ethnic enclaves form within the city. This does not mean that cities are bad or should be avoided. Instead, we are observing that the economies of scale that cities offer have a price. Cities are economically productive places, engines of innovation, and seem to have network effects—at least up to a point—such that additional people can create exponential economic productivity. One reason for this is infrastructure. Laying the pipes and electrical grid to furnish a million people with water and electricity in a geographically concentrated city is much easier than laying down the infrastructure for 1,000 small towns, each of which has 1,000 residents. The environmental footprint and infrastructure costs are typically much larger per resident in 1,000 hamlets than they are in a thriving metropolis such as London or Sydney.Footnote ⁸

Similarly, smart or creative people who live around many other people who share their abilities and interests can bring their ideas together in a way that benefits all of them and has positive externalities for the world.Footnote ⁹ This is especially true when the average IQ of a population is high and when market forces incentivize people to share their ideas in institutions such as clubs, universities, and firms.Footnote ¹⁰

The move to cities also has costs. These include a tendency for pro-social traits to be less rewarded than they would be in a small and stable group. Living in small and stable groups forces us to interact repeatedly with the same people, which allows us to find and reward trustworthy people and punish free-riders.Footnote ¹¹ This is especially challenging in large cities where we are less likely to see the same people over time and less likely to suffer social sanctions for bad behavior.

Apart from the challenge of establishing stable norms of cooperation in large and heterogeneous cities that have a steady stream of people moving in and out, cities can also be alienating. As population density increases, the price of desirable real estate rises. People tend to live in smaller housing units with less access to nature and less of a sense that they belong to a neighborhood. They often feel less connected to anything that resembles a community. This is part of what social scientists mean when they say that social capital has declined in modern American cities.Footnote ¹²

Another effect of moving to cities is declining fertility. In modern liberal societies, people tend to move wherever they can make the most money: usually, to cities. That means people move to and create the conditions for places that have less social capital than do traditional neighborhoods. Moreover, these cities lack the social pressure that traditional communities exert on their inhabitants to form a family rather than chasing financial success. Although traditional communities may exist within cities, they are not the norm. Cities also increase the cost of raising children. Fertility has declined not only in cities, but everywhere that wealth and opportunities for women have increased.Footnote ¹³ However, in wealthy countries around the world, people living in cities have significantly lower fertility rates than people living in less dense neighborhoods.Footnote ¹⁴ Cities are probably the natural result of specialization and trade. They exist under liberal and illiberal regimes. To the extent that liberalism encourages people to move out of communities and into cities in the pursuit of profit, though, this process may be especially prominent in liberal societies, even if it happens to some extent in all societies that are large, prosperous, and have robust markets. Fertility declines are not necessarily a problem, especially when infant mortality declines enough that most people who are born survive into adulthood. But in the largest and wealthiest cities around the world, fertility is far below replacement, which presents obvious long-term problems.

To prevent this problem, nonliberal governments sometimes discourage the move to cities. For instance, the Chinese government regulates internal migration into cities to prevent mass urbanization and to maintain a sense of social order. It does so through the removal of basic rights. As a result, Chinese people who reside in cities without governmental permission are de facto illegal aliens.Footnote ¹⁵ Liberalism, however, cannot resort to these measures without violating some of its core principles, such as freedom of association and contract. While mass urbanization may affect all advanced economies, liberal governments have fewer policy instruments to regulate its undesirable effects—including alienation, decreased social capital, and low fertility—than do nonliberal regimes.

III. Immigration

One of the most obvious trends in contemporary liberal societies is the move toward open borders. In the United States, mass migration began in the late-nineteenth century, but most migrants came from Europe. After World War II, and especially in the 1960s, mass migration accelerated and, for the first time, large numbers of people from outside of Europe—including Africa, Asia, South America, and the Middle East—migrated to liberal democracies such as the U.S., Canada, Australia, New Zealand, Sweden, the United Kingdom, and other European countries. Mass immigration has never been a popular policy in the West, even if many citizens in European countries support modest levels of immigration among skilled workers and people fleeing war.Footnote ¹⁶ However, there is an emerging consensus among liberal theorists that freedom of movement, including the movement of people across borders, is a moral right, with restrictions of movement needing justification.Footnote ¹⁷ While there are liberal critiques of mass migration,Footnote ¹⁸ it is increasingly common among liberal academics and progressive activists to support mass migration, even in the face of popular opposition.

Apart from arguments that derive from principles or ideology, liberalism as a political system tends to reward large corporations that import the lowest-cost workers they can find, even if they come from outside a nation’s borders. The free market aspect of liberal institutions tends to concentrate capital in large firms.Footnote ¹⁹ These firms then lobby governments to import cheap labor from abroad. This is good for the individual firms since they can pay lower wages. It is also good for consumers to the extent that it lowers the prices of consumer goods. Over the long run, though, apart from its employment effects on the native population, the aggregate effect of mass migration on the country in which it occurs seems to be to lower social trust.Footnote ²⁰ To take a simple example, Scandinavian countries—including Denmark, Norway, and Sweden—have had historically high levels of social trust, but only Sweden has seen trust fall recently, at precisely the time when they admitted large numbers of (especially low-skilled) immigrants from Africa and the Middle East.Footnote ²¹

One explanation for why mass migration can lower social cohesion is that we are tribal creatures who search for cues of trustworthiness. These cues can come from a common ethnicity, which can include similarity of ancestry, language, religion, or values. Just being a citizen of a large and diverse state is unlikely to elicit much fellow feeling. Ethnicity is a much more salient set of traits. Ethnocentrism is likely an adaptive trait,Footnote ²² even if it can have bad consequences in some contexts, such as motivating people to engage in genocide over disputed territory. While people are somewhat malleable in their ability to tolerate and cooperate with others who are unlike them,Footnote ²³ there are limits to toleration and cooperation. Liberal political societies have been testing these limits to such an extent that social trust has fallen in Western countries with especially high levels of immigration from poor countries.Footnote ²⁴ Indeed, recent evidence suggests that support for immigration falls when immigrants are ethnically distinct and poor.Footnote ²⁵

Despite popular opposition,Footnote ²⁶ political parties in liberal societies tend to collude with corporations to import workers and voters.Footnote ²⁷ Policymakers in liberal democracies are strongly influenced by private corporations who finance their campaigns and apply pressure for policy favors. Corporate executives at large firms favor mass migration because this allows them to select workers from a larger pool.Footnote ²⁸ One consequence is an increase in highly skilled workers. Another is an increase in low-skilled workers to whom firms can pay lower wages. However, corporations, policymakers, and elites in academia and journalism who shape public opinion and craft policy, often ignore the long-term demographic effects of migrant workers on the larger political society in which they live. These effects, whether positive or negative, are externalities; that is, they are unintended byproducts of an otherwise mutually beneficial exchange either between corporation and migrant worker or between a political party and the beneficiaries of that party’s policies. According to the “deep roots” literature in economics, patterns of migration shape the long-term prosperity of countries by altering institutions and the nature of the people who occupy them.Footnote ²⁹

Immigration is not a uniquely liberal phenomenon, though. Policymakers in nonliberal regimes craft immigration to fit their interests and values,Footnote ³⁰ but because they do not necessarily have to worry about elections, they are not as dependent on short-run profits or the approval of profit-seeking firms. Nor do they always subscribe to principles of universal rights. Because rulers in nonliberal regimes govern for longer periods and often without democratic legitimacy, they have stronger incentives to pay attention to the long-term costs of immigration, especially costs that can endanger their rule, such as social instability and conflict. Moreover, because nonliberal regimes do not always offer political rights to immigrants, they can more easily reverse immigration flows.

Another avenue along which liberal institutions encourage mass migration is that domestic and international laws recognizing universal rights tend to produce norms among citizens that encourage those rights to be indefinitely extended. Liberal political institutions seem to encourage people who think of themselves as good citizens to expressively support candidates who exalt the values of diversity and toleration and who normally support mass migration.Footnote ³¹ It is hard to know whether liberal political societies tend to foster this kind of thinking or it is just a fad in Western countries over the past few decades. However, once mass migration becomes a reality, it does seem natural that social norms would change in ways that reduce the patriotic and nationalist sentiments that signal a unique attachment to a people and place. More importantly, nonliberal regimes that reject universal human rights, human equality, and other ideals associated with liberalism can adapt with restrictive immigration policies in ways liberal institutions cannot without violating their core commitments.

IV. Character Traits and Social Norms

In Twilight of the Idols, Friedrich Nietzsche speculates in 1889 that the fight for freedom tends to make people responsible, virtuous agents, but that attaining freedom makes them complacent and weak:

While these passages can be interpreted in many ways, a central idea is that a lack of struggle makes most men weak and that weaklings lack the vitality needed to build and preserve the institutions that allow us to prosper. If a lack of physical vigor and intellectual virtue results from any system that produces wealth and prosperity, Nietzsche’s point is less about liberalism than it is about institutions that promote wealth and the vices that wealth enables.

However, we may extend Nietzsche’s conjecture from character traits to social norms. It is possible that because of its foundational commitment to freedom and equality as well as the increasingly loose interpretations of these concepts, social norms weaken under liberal institutions. According to Patrick Deneen, “because self-rule was achieved only with difficulty … the achievement of liberty required constraints upon individual choice. The limitation was achieved not primarily by promulgated law … but through extensive social norms in the form of custom.”Footnote ³³ “Ironically,” Deneen argues, “as behavior becomes unregulated in the social sphere, the state must be constantly enlarged through an expansion of lawmaking and regulatory activities.”Footnote ³⁴

To be sure, Nietzsche’s conjecture that the traits required to produce liberal institutions are undermined by those very institutions is speculative. Deneen’s idea that social norms are undermined by liberalism is also a hypothesis that he does not supply decisive evidence for. As Cass Sunstein reminds us in a rejoinder to critics like Deneen:

This is an important point. To show that liberalism produces certain outcomes rather than merely correlates with them, we need to identify specific mechanisms. No evidence in this realm can be as decisive as a mathematical proof, but we think some conjectures are more plausible than others.

One claim we try to justify in this essay is that liberal political institutions foster the emergence of social norms surrounding reproduction in ways that threaten their sustainability. The freedom to form any kind of family or to identify as any gender is increasingly common in wealthy liberal societies. Even if these norms do not necessarily result from liberal institutions, once they emerge, liberals can do little to alter them without violating their core liberal commitment to state neutrality. However one views traditional family norms, it is easy to see how radical permissiveness in this area—the sense that one is free to do anything, regardless of the social consequences—can contribute to subreplacement fertility.

V. Maladaptive Behavior and Luxury Beliefs

There is some historical evidence that wealth and liberal attitudes about family tend to depress fertility by increasing indulgence in maladaptive behaviors that are less available in societies with more scarcity and less safety.Footnote ³⁶ Many authors have pointed out the parallels between the cultural malaise of modern Western societies and the decadence of the late Roman Empire, which saw more wealth, increased sexual freedom, and decreased fertility.Footnote ³⁷ The poet Juvenal explains the decadence of the Roman empire as follows:

It is not only maladaptive behaviors that wealth seems to invite. Our beliefs may also become exotic rather than accurate in times of opulence. Rob Henderson recently coined the term “luxury belief” to designate beliefs people form—or at least, publicly display—to signal that they are part of the intellectual elite.Footnote ³⁹ These beliefs are similar to luxury goods such as designer clothes and jewelry. In order to be costly, though, such beliefs must be difficult to form; for example, in some cases, it requires high intelligence to form luxury beliefs in part because they conflict with reality itself and require cognitive dissonance. Anyone can believe the sky is blue, but it takes a clever person capable of a particular kind of mental gymnastics to believe there are no average differences between men and women or that all humans have the same natural capacities, so that only oppression and injustice explain different outcomes. Yet these (and other similar) beliefs are now common among the intellectual elite in the U.S. and U.K.Footnote ⁴⁰ It is not that intelligent people are more likely to hold false beliefs; they are just better at rationalizing them.

In all ages, people wish to distinguish themselves as members of some groups and not others. Intergroup competition is, after all, a key component of human evolution.Footnote ⁴¹ Notably, in wealthy liberal democracies with competing political cultures, some elites extol a kind of radicalism in part to build an identity and distinguish themselves from their opponents. For example, it has become commonplace in modern liberal societies to hold that all gender roles should vanish because they are the product of patriarchal oppression, not of human nature or human reproductive imperatives. Faith in such radical ideas signifies membership in an elite class of peopleFootnote ⁴² and deviation is often punished through social sanctions in the workplace and censorship on social media.Footnote ⁴³ Certain beliefs allow people to signal their membership in powerful coalitions. Having the right beliefs is socially rewarded within those coalitions, even when it is clear to outsiders that the beliefs are false.Footnote ⁴⁴ In this sense, expressing a false belief can be advantageous to the extent that it signifies one’s membership in a specific group.Footnote ⁴⁵

Luxury beliefs held by many of the elite in modern liberal societies have at least two important consequences. First, they foster social polarization between progressives and conservatives (including nationalists, populists, and traditionalists), which in turn lowers social trust and cohesion. Second, those beliefs can spread maladaptive norms to those who imitate the behavior and attitudes of liberal elites.Footnote ⁴⁶ Indeed, this seems to be taking place. In the United States, for instance, people who hold liberal beliefs have considerably lower birth rates than conservatives, a trend that is widening in recent decades.Footnote ⁴⁷ To the extent that reproductive fitness is tied to biocultural continuity,Footnote ⁴⁸ including institutional continuity, this trend puts a question mark on the long-term evolutionary sustainability of liberal institutions.Footnote ⁴⁹ To be sustainable, liberal institutions would need to foster both group cohesion and reproductive fitness—and they would have to do it better than nonliberal institutions.

Few liberals defend liberalism by appealing to its fitness-maximizing capacities or evolutionary stability. A prominent exception is Friedrich Hayek.Footnote ⁵⁰ Liberal groups, in his view, will tend to expand and replace groups with tribal norms via cultural group selection.

VI. Demographic Challenges

Current evidence, however, does not support Hayek’s theory that wealthier societies will have higher fertility rates.Footnote ⁵¹ The populations of the most-developed market economies—in particular, liberal democracies—have subreplacement fertility rates. By contrast, many populations of lower-performing economies, often living under nonliberal regimes and guided by religious ideology, display remarkable demographic growth. A similar dynamic can be seen within the West. For instance, subcultural and religious groups like the Amish, who reject modern technology and lifestyles, have birth rates that allow them to double their population every twenty years.Footnote ⁵² Religious fervor is a strong predictor of population growth. Global demographic trends reveal that religious and nonliberal populations are increasing substantially relative to liberal and secular populations.Footnote ⁵³ If these trends continue and if religiosity and political orientation are moderately heritable,Footnote ⁵⁴ nonliberal political institutions may very well displace liberal political institutions, even if they produce less wealth. Cultural selection strongly influences who reproduces and, consequently, what kinds of people populate a society.Footnote ⁵⁵

To tackle the issues of subreplacement fertility rates and labor shortages, Western governments often bring in immigrants from high-fertility areas, such as sub-Saharan Africa—whose population is expected to triple by 2100—or from areas with large populations such as Asia or the Middle East. While Western governments may expect these immigrants to adhere to liberal norms of gender equality and individualism, it is unclear whether this will happen. Immigrants who retain fertility-promoting beliefs will have evolutionary advantages over low-fertility Western peoples. We should expect those who uphold fertility-enhancing norms to increase in size and political influence, thus challenging liberal institutions. Notably, the current rise in identity politics within the West reflects, in part, demographic changes; such changes might bring the rejection of current institutions that are derided by traditionalists.

Some scholars have argued that subreplacement fertility rates in the West may be a temporary phenomenon.Footnote ⁵⁶ If so, liberalism is not under demographic threat. These scholars maintain that more gender equality can solve the fertility problem brought by female emancipation. They claim that with more equality between the sexes or with more economic growth among women, we would be able to combine work and education with having children. Yet, when comparing societies across time, this view is not supported.Footnote ⁵⁷ The countries with the highest levels of gender equality and highest per capita income, such as the Nordic countries, have not seen a substantial increase in fertility. Quite the contrary.

Low fertility is not unique to liberal democracies. Population growth worldwide is slowing, with the exception of Africa, whose population continues to grow.Footnote ⁵⁸ Declining birth rates are usually attributed to the expansion of female education, rising female income, and access to contraception.Footnote ⁵⁹ Overall, rising living standards and global markets increased women’s freedom and weakened religious beliefs; together, these account for some fertility declines due to a desire to have fewer children rather than an inability to have children.Footnote ⁶⁰ Decreases in infant mortality due to medical innovations have led both men and women to want fewer children, in part because more kids survive into adulthood. Wealthier people also have fewer kids because they do not need children to help with physical work such as farming and because the relative cost of kids is higher when there are opportunities that were unavailable in the past.Footnote ⁶¹

Some liberal regimes, including Germany and Japan, have enacted policies to boost birth rates.Footnote ⁶² However, none of them has raised fertility to replacement levels. Moreover, because these policies focus on material incentives rather than on how culture affects fertility, they are unlikely to have much effect. For example, some economists argue that using policy levers to lower the cost and burdens of childcare and to make jobs more flexible, may incentivize parents to have more children.Footnote ⁶³ Many of these kinds of policies already exist in Nordic countries, though, where fertility among the native (nonimmigrant) population remains well below replacement levels. Perhaps in the future a combination of family policy and a dramatic decrease in the relative cost of raising children—due to technological innovations or rising income—will lead to liberal societies again seeing population stability or growth. While this is conceivable, there are two problems with this possibility. First, financial costs alone are unlikely to convince people in liberal societies to significantly increase their birth rates. Second, it is difficult to describe policies that promote family and fertility as liberal to the extent that they prioritize and subsidize a particular kind of lifestyle, one of the sort that promotes getting married and having children.

Religion and nationalism seem better equipped at tackling the demographic problem.Footnote ⁶⁴ Religiosity is a key predictor of fertility; worldwide reproduction patterns show that religious populations reproduce much more than secular ones.Footnote ⁶⁵ Indeed, as Jonathan Haidt argues, “societies that forgo the exoskeleton of religion should reflect carefully on what will happen to them over several generations. We don’t really know, because the first atheistic societies have only emerged in Europe in the last few decades. They are the least efficient societies ever known at turning resources into offspring.”Footnote ⁶⁶ It is worth noting, however, that as religious institutions in liberal societies such as Sweden, England, and the U.S. have become more politically liberal, it is unclear whether religion per se will promote birth rates, or only specific types of religion that emphasize the value of family, or that have an account of a civilization that is worth preserving and extending into the future will promote birth rates. Some secular thinkers have sought to emulate the power of religion by packaging political ideas into a bundle that includes costly signals such as rituals and a sense of transcendent meaning.

Nationalism, too, can have a powerful impact on reproduction. Israel, for instance, is the only developed country with high fertility, thus showing that advanced societies are compatible with elevated fertility. The Israeli government not only promotes birth rates via financial incentives, but also enforces nationalistic duties to defend the existence and autonomy of the Jewish people. It is, after all, a country with a strong sense of collective identity and under permanent threats from neighboring groups. In the end, while religious Jews in Israel have the highest birth rates, even secular Jews have fertility rates that are above replacement.Footnote ⁶⁷ Religiosity and nationalism are arguably more efficient than material incentives at boosting reproduction, for the former shape our moral compass, while the latter simply help satisfy desires that fall out of fashion in a liberal society. By shaping people’s moral compass in ways that make them see reproduction as a good in itself or as a duty, religion and nationalism make reproductive habits less sensitive to material conditions. Religion and nationalism can foster high birth rates under situations of scarcity and abundance, which produces long-term population growth or at least population stability.

Liberalism’s sustainability problem is, then, as follows. Liberals cannot impose a fitness-enhancing vision of the good life without violating their commitment to pluralism and individual liberty, so they must tolerate ways of life that minimize fitness. Nonliberal regimes, by contrast, can experiment with many different views of the good life and enforce them on societies without liberal restrictions. The Hungarian government, for example, stresses the importance of being a part of European civilization, imposes strict immigration restrictions, and tries to imbue its citizens with a sense that they have a duty to carry forward the torch of their nation’s history and identity. While Hungary is not a dictatorship, it is distinctly nonliberal in its orientation.Footnote ⁶⁸

Of course, one may argue that there is more experimentation in liberal, open societies. This is generally true, though it can be difficult to implement certain restrictive solutions—from compulsory vaccination to governmental surveillance—while respecting individual liberties. Nonliberal governments, by contrast, lack such constraints. They can solve large-scale collective action problems by imposing novel codes of conduct from the top. Such governments are also constrained in experimenting with novel codes, for if an experiment goes wrong, it can end their regime. Nonliberal governments often fail in spectacular ways, but the room for moral experimentation in politics is often wider in nonliberal regimes than liberal regimes. A prominent example of this flexibility is the Chinese government’s change from communism to market autocracy in the late-twentieth century and its recent efforts to promote fertility by restricting people’s liberties in fundamental ways.

Perhaps more importantly, nonliberal governments can shape people’s values by promoting a comprehensive conception of the good life. This is important to the extent that fertility is correlated with having a sense of meaning. While the liberal rejection of a specific conception of the good can be liberating for some people, it can also create an environment in which many fail to see themselves as part of a civilization that is worth sustaining. Fyodor Dostoevsky wrote eloquently about the loss of meaning in modern Europe as religious faith began to wane. A character in Dostoevsky’s The Brothers Karamazov observes:

Without a sect, tribe, or tradition to fight for, it may be difficult for many to see why they should bother having children or making the kinds of sacrifices required by a lasting civilization. Nevertheless, liberal polities cannot prioritize the formation of families over the satisfaction of any other desires or preferences. Instead, in order to remain liberal, a state must stay neutral between different conceptions of the good that form the basis of a meaningful life and often give us reasons to have children.

VII. Social Trust and Cooperation

Sheer reproduction, however, is not the only element that confers advantages to social groups. Although a larger group size is often a favorable adaptation,Footnote ⁷⁰ the ability to cooperate is also critical. Smaller groups can outcompete bigger groups if the former have better cooperation strategies. But how do we predict cooperation in social and political settings? One answer is social trust. Footnote ⁷¹

Social trust facilitates cooperation and represents generalized trust in strangers within society. Social groups with members who can trust one another can better solve collective action problems, for example, by voluntarily contributing to public goods and refraining from violating mutually beneficial rules when nobody is watching. Indeed, “individuals who lack faith in their peers can be expected to resist contributing to public goods, thereby inducing still others to withhold their cooperation as a means of retaliating.”Footnote ⁷² Predictably, high levels of social trust are associated with greater economic growth, less corruption and crime, and more stable institutions.Footnote ⁷³

Social trust is in steep decline in the United States, though, which is the epicenter of liberalism. To take one measure, in the early 1970s, around half of Americans declared that most people can be trusted; today, less than a third do.Footnote ⁷⁴ As Kevin Vallier argues, this decline is causally linked with political polarization, which is growing quickly in America.Footnote ⁷⁵

However, not all liberal democratic countries have seen sharp declines in social trust. Northern European countries such as Norway, Sweden, and Finland remain among the most trusting countries in the world. To complicate things further, autocratic China is also among the countries with the highest social trust.Footnote ⁷⁶ Clearly, political institutions and their ideology are not the only factors that influence trust.

A crucial feature of high-trust countries is ethnic homogeneity. Although scholars disagree about the causes of the decline in social trust, it is well-established that there is a “statistically significant negative relationship between ethnic diversity and social trust across all studies.”Footnote ⁷⁷ Gene-culture co-evolution can explain why ethnic tribalism is so prevalent and resilient. Ethnicity comprises group traits such as phenotype, language, and mechanisms of social control, including religion and other sacred beliefs.Footnote ⁷⁸ Humans use these traits as markers and mechanisms to produce intragroup cooperation.Footnote ⁷⁹ For this reason, many people are reluctant to change their identities and abandon their collective interests. This unwillingness generates intergroup conflicts (and distrust), especially when very different groups occupy the same space. The cultural mixing of different ethnicities often produces unclear norms and symbols, thus fostering a decline in social trust, including trust in one’s own group members.Footnote ⁸⁰ Tribalism may well reemerge in liberal societies as a response to this decline. As Julian Culp puts the point, “exclusivist moralities are characterized by relatively high levels of cooperation, reciprocity, and solidarity among those who are part of the same tribe or in-group.”Footnote ⁸¹

Liberal institutions could try to prevent ethnic conflict and thus reduce political polarization and increase social trust by curbing immigration. As explained above, though, these institutions have moral and economic incentives to increase diversity via immigration. Indeed, the U.S. is perhaps the strongest example of this trend toward open borders, but western European countries also increasingly rely on immigration. As a result, most European countries have seen a rise in popularity of anti-immigration nationalist parties.Footnote ⁸²

If liberals wish to foster intergroup cooperation in open societies with diverse populations, they need to promote some form of social solidarity and to enforce it. They need to engage in something like nation-building. Highly diverse societies, however, require more than the simple promotion of “openness” and “toleration” to foster cooperation. Not every culture that emerges in liberal societies (or arrives via immigration) will value openness and toleration. A mere commitment to toleration is unlikely to motivate and bind people in ways that a religious commitment or a patriotic connection to a national destiny can. Moreover, liberal governments, if they are to remain liberal, need to punish deviants in ways that do not violate their fundamental commitments to freedom and equality, to toleration and openness. We already see strong signs in liberal countries like the U.S. that governments and large corporations (for example, Amazon, Google, YouTube, and Facebook) often collude to silence and punish people who express opinions that deviate from progressive orthodoxy.Footnote ⁸³ Ultimately, the level of punishment necessary to unify vastly heterogeneous populations under the same polity may be too high even for most nonliberal worldviews (for example, communitarianism or conservatism). It would likely take extremely repressive measures to create and maintain cherished ways of life, enforce a common identity, and prevent the formation of tribal factions in the absence of a common understanding.

Liberal societies, then, seem to create the conditions—at least over the long run—for polarization and low social trust. As Vallier points out, “as people trust each other less,” polarization “creates a vacuum the state will fill. When trust dies, it’s replaced by coercion and control.”Footnote ⁸⁴ As such, it is difficult to see how liberalism can endure if it cannot impose a way of life that fosters intergroup cooperation within society. In effect, to prevent political dysfunctionality, liberal governments may have to replace vague hopes that very different kinds of people will cooperate with a coercively enforced vision of the world. As cooperative groups tend to outcompete dysfunctional groups, liberal societies will face hard choices.

Liberal states are thus at a disadvantage when competing against more cohesive states in the international system.Footnote ⁸⁵ Without invoking evolutionary considerations, John Mearsheimer summarizes why the liberal order is likely to fail:

Some government officials in both China and the United States seem to agree with this. In 2012 the U.S. Department of Defense commissioned a study called “The Strategic Consequences of Chinese Racism.”Footnote ⁸⁷ The report was not made public until the U.S. government was compelled by court order to release it in 2022.

According to the report, Chinese government officials are puzzled by—but also celebrate—what they consider to be the self-flagellation of many in the U.S., and the West more broadly. They mock the fact that, as they claim, American educational and cultural institutions denigrate its majority white population and disparage its culture and history.Footnote ⁸⁸ They “see multiculturalism as a sickness that has overtaken the United States, and a component of U.S. decline.”Footnote ⁸⁹ By contrast, China is “not plagued by self-doubt or guilt about its past.”Footnote ⁹⁰ In China, “racism will never be seen as a problem”; instead, racism is

One implication of the report is that “[f]rom the Chinese viewpoint, all of this conspires to cause the breakdown of American society…. [Consequently], the Chinese government may have less of a desire to confront the U.S. due to the expectation that it will collapse of its own internal discord.”Footnote ⁹² We are not making any predictions here about whether the U.S. or any other liberal countries in the West will collapse. We are instead emphasizing that, for the reasons mentioned above, liberal political institutions are more precarious than the previous two centuries have led us to believe.