That’s disconcerting for several reasons. For one thing, it means that large numbers of Americans believe they and their children can no longer thrive in the United States. That signals the rise of widespread hopelessness, which can easily become a self-fulfilling prophesy, as individuals and families stop striving (and making sacrifices) for a better future they’re convinced is unattainable. That’s a recipe for (further) economic stagnation, psychological depression, and the social pathologies that tend to accompany both.

But the political consequences could be even more ominous.

People who believe their lives are likely to get worse over time tend not to accept that fate complacently. On the contrary, pessimists often end up searching for and tempted by would-be saviors — individuals or movements who promise to break the pattern of decline. But because the status quo is implicated in the decline, the individuals or movements that inspire the greatest hope for improvement are the often ones who threaten to do the most damage to the established order of things in preparation for a miraculous leap into a new and dramatically better world. Pessimism is a potent incubator of political radicalism.

We’ve gotten a taste of such radicalism in Trump’s vaguely defined promise to “Make America Great Again,” which has been attached to proposals for radical shifts in immigration, trade, and foreign policy. Whether Trump loses in November or wins and then fails (as he almost certainly would) to make noticeable improvements in the lives of his pessimistic voters, those voters are bound to grow more pessimistic, and hence more radical, in future elections.