"A new Gallup poll showed that just 33 percent of Americans are satisfied with the nation's position in the world today. This is down from 65 percent in 2000. As Donald Trump and Joe Biden—two historically old and deeply unpopular presidential candidates—square off yet again for America's top job, it's not hard to understand these sentiments. America is in decline in the 21st century in measure after measure, from numerous public-policy failures, to increasingly dysfunctional politics, to an epidemic of mental health issues among young people. This predicament raises two essential questions: Is America's downturn merely another dip in a long arc of non-linear, yet essentially upward, progress? Or is it, rather, the first phase of steep and irreversible national decline? The answer lies with the American people. Like all nations, America is, above all, the hearts and minds of its people. And the trend line is moving hard in the wrong direction: Things are getting worse, not better. Tribalism is intensifying. Social-media platforms are getting smarter at manipulating human cognition. The political system's defects are worsening. And America's public-policy failures are deepening."