The primary theme of “People Like Us” is the difference between a diverse population and a truly culturally mixed society. The essay never suggests that the United States is not diverse; it provides numerous examples of the various cultures and communities that exist throughout the nation. This evidence, however, leads the author to conclude that the country does not consist of an evenly mixed population of people living different lives. Instead, the American population comprises distinct pockets of people, each of which is to a large extent internally uniform. In some areas, these pockets exist along broad geographic lines, such as the prevalence of socially liberal views in urban and coastal areas versus the more conservative rural population in interior states. In other areas these distinctions exist on a neighborhood-by-neighborhood level. In addition to discussing geographic segregation, the article argues that people tend to choose people similar to themselves as marriage partners, work in roles that conform to their personalities, and consume the same media as people with similar backgrounds.

Brooks’s argument centers mostly on ideological—or at least cultural—diversity. Although he briefly notes the persistence of racial segregation in the post-Jim Crow era, he does not discuss how that segregation has evolved over time.