The document discusses the influence of various media sources on American youth and the formation of public opinion over time. It finds that in the 1950s, home and school had the greatest influence, while in later decades peers and television became more influential. The rise of new media technologies has further decreased other influences. The mass media, including various sources like newspapers, radio, television and the internet, plays a major role in shaping political views and priorities in the U.S. while also serving important democratic functions, though it also faces criticisms around biases and effects on public discourse.