The 1922 book Public Opinion is Lippman's assessment of functional democratic government and the role of citizens in a democracy ; it examines the dilemmas presented in such a revolutionary period of history and places doubts on people's ability to govern themselves. He emphasizes the media's function in shaping public perceptions ad warns against the power of propaganda. Lippman's exploration and endorsement of modern democracy have made his body of work a staple in the field of political science.