Bangladesh, July 13 -- As the United States marks 250 years since declaring independence, the occasion might have been expected to inspire a renewed sense of national confidence. Independence Day has long been associated with patriotic celebrations, fireworks, and speeches celebrating the ideals of liberty, democracy, and opportunity. Yet beneath the familiar symbolism, a more complicated reality has emerged. Surveys, political debates, and widening social divisions suggest that many Americans are questioning not only the direction of their country but also the promises that once defined it.

The anniversary arrives at a time when faith in American institutions has weakened, confidence in democracy has declined, and optimism about the fut...