The prevalence of positive illusions is one of the most well-established findings in psychology. Most people have an exaggerated view of their own abilities and expect that more good things—and fewer bad things—will happen to them than is likely.

Despite being unrealistic, such beliefs have benefits: Overly positive people are happier, cope better with adversity, and think they have more control over their life. Believing that things are a little better than they actually are may be necessary for robust mental health.

In a similar way, many citizens hold overly positive, but possibly necessary, beliefs about their country. A sense of national pride can foster community and bring people together, and it’s often a sign of a thriving democracy. In the United States, one source of patriotism is American exceptionalism—the idea that the U.S. is a unique, and uniquely superior, nation. With its origin as a democracy in a world of kingdoms and its emphasis on freedom and opportunity, this narrative goes, the American system is out of the ordinary.

Among the young, that belief is rapidly dying. Since 1976, a large nationally representative survey has asked U.S. high-school seniors, 17 and 18 years old, whether they agree that “Despite its many faults, our system of doing things is still the best in the world”: a fairly succinct summary of American exceptionalism. In the early 1980s, 67 percent of high-school seniors agreed that the U.S. system was the best. By 2022, only 27 percent did. Thus, only one out of four American teens now agrees that their country is exceptional.

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The decline appears to be mostly untethered to national events. Belief in American exceptionalism went down during the Great Recession of the late 2000s, and also during the economically prosperous years of the 2010s. It declined when the U.S. was at war and also when it was at peace. It declined as income inequality grew rapidly, from 1980 to 2000, and also as inequality moderated after 2000.

Support for the idea is now particularly unpopular among liberal teens. As recently as the late 1990s, a majority had agreed that the U.S. system was the best. By 2021–22, that had shrunk to 14 percent—only one out of seven. (Belief in American exceptionalism has declined among conservative teens as well, but much less so: 47 percent of conservative teens believed in the idea in 2021–22.)

Even the belief that the founding of the United States was a positive development seems to be on the way out: A recent poll conducted by the Democracy Fund asked Americans if the Founders are “better described as villains” or “as heroes.” Four out of 10 Gen Zers chose “villains,” compared with only one in 10 Boomers. If your country’s Founders are the bad guys instead of the good guys, it becomes much harder to believe that its system is the best in the world—or even worth defending. (Ideas about America are hardly the only beliefs that have bent toward pessimism among American youth in the past two decades. In early 2002, for instance, 23 percent of high-school seniors agreed with the statement “When I think about all the terrible things that have been happening, it is hard for me to hold out much hope for the world.” In early 2019, 40 percent agreed.)

Dour views of the nation’s status and possibilities may shape its future. Gen Z may be disillusioned, but it is not, by and large, nihilistic: Today’s young adults are also more interested in taking action than previous generations. From 2014 to 2021–22, an increasing number of high-school seniors agreed that protesting and voting could have “a major impact on how things are run in this country.” Voter turnout among young adults has been higher among Gen Z than previous generations at the same age, and political protests appear to have become more frequent in the eight or so years since Gen Z arrived on college campuses.

That, of course, could yield positive changes. One of the most important American ideals, arguably, is that the American project is unfinished, and that society can be made better, generation by generation. Throughout U.S. history, discontent and even righteous anger have often been important correctives to overly broad or unthinking sentiments about the country’s goodness, which, when unchallenged, can perpetuate injustices.

But many of Gen Z’s members seem convinced that radical change is necessary—to the model of government, to the economy, to the culture. In a 2020 poll I analyzed for my book Generations, three out of four American Gen Zers—more than any other generation—agreed that “significant changes” were needed to the government’s “fundamental design and structure.” Nearly two-thirds believed that America was not “a fair society,” again a higher rate than older adults. In a 2018 Gallup poll, more 18-to-29-year-olds had a positive view of socialism (51 percent) than of capitalism (45 percent). Some of the ideals, and idealism, that were commonly accepted in previous generations seem to have a looser hold over young adults today.

Why has Gen Z turned so definitively toward disillusionment and away from seeing their country as superior?

One reason may be their mental health: Twice as many teens and young adults are depressed than in the early 2010s. This is a tragedy—and it’s likely to have wide-reaching effects. Depression isn’t just about emotions; it’s also about cognition. By definition, depressed people see the world in a more negative light. They are less likely to see the positive, including in their country. Increases in depression are larger among liberals, consistent with the larger decline in their belief in American exceptionalism.

Changes in news consumption may also play a part. When newspapers were read on paper, all of the news—positive and negative—was printed together. Now negative news is king. Negative articles are almost twice as likely to be shared on social media as positive articles. Social-media algorithms push angry and divisive content. With Gen Z getting most of its information online, it is viewing the country through a negatively skewed funhouse mirror.

A third reason may lie in the shifts in high-school American-history curricula. Some—typically liberal—states now spend more time than they once did on the more deplorable facts of the nation’s history, such as the internment of Japanese Americans during World War II, the massacre of Native Americans, and the Founders’ ownership of slaves. That coverage lays out facts students need to know, but, especially if these events are emphasized more than the country’s more noble endeavors, it may also undermine feelings of national pride.

[Read: Are Gen Z men and women really drifting apart?]

Finally, Gen Z’s facility with social media may itself be coloring the generation’s views. Gen Z has learned that making a problem look as big and awful as possible is a highly effective way of getting traction on social media. Many problems are often portrayed as profound and systemic, fixable only by fundamental rethinks and institutional purges. It makes everything seem worse than it is.

My worry, as a social psychologist who has studied all of the living American generations, is that these various forces—and the pessimism they have generated —could move Gen Z to change systems that are not necessarily broken. That’s especially relevant as this generation comes of age and rises toward political power. Despite the common perception that the system is “rigged” and young people will never attain the wealth Boomers did, for instance, the Federal Reserve of St. Louis recently found that Millennial and Gen Z young adults actually have 25 percent more wealth than Boomers did at the same age. Inflation-adjusted median incomes for American young adults are at all-time highs, and poverty rates for children and younger adults are lower than they were in the early 2000s. The social-media-driven negativity machine may have prevented Gen Z—and all of us—from seeing the good news.

Just as the positive views we have about our individual selves may be exaggerated, the idea that the United States is uniquely superior is also, at least in part, an overly optimistic illusion we tell ourselves as a country. But like our positive self-illusions, patriotism also has its benefits, including a more satisfied citizenry and more political stability. With Gen Z unconvinced of the country’s exceptionalism and willing to take action, the U.S. may, in the coming decades, witness an era of extraordinary political change.