David Riesman's The Lonely Crowd explores the links between social character—the ways in which members of a society are similar to one another—and social structures. He argues that as the United States became predominantly consumer-driven, rather than production-driven—particularly after World War II—American social character changed. While pre-war Americans had based their behavior on their own internal values and beliefs, post-war Americans were becoming other-directed, with external groups including peers and the media now a key influence on the way they behaved. Riesman's work popularized sociology, helping to establish it as an academic discipline, and today it provides a fascinating window into the 1950s American psyche.