We have argued that most citizens are not located in politically homogeneous groups, that the experience of disagreement is not a rare event, and hence that political communication among citizens carries the potential for a meaningful process of political deliberation. At the same time, theories of political communication have suggested that disagreement might produce confusion, ambivalence, and political withdrawal. In short, we would appear to be confronted by a democratic predicament: Either citizens are political enthusiasts who are isolated and protected from encounters with divergent perspectives, or they are political refugees who have withdrawn from the uncertainty and discomfort of disagreement. This chapter examines the consequences for political engagement that arise due to patterns of political diversity within the communication networks connecting citizens to one another. How do politically diverse preferences within communication networks affect political opinion, cognition, and levels of ambivalence on the part of individuals within the networks? How are these heterogeneous preference distributions related to levels of political engagement and turnout? We address these questions with data drawn from the 2000 National Election Study.

If communication among citizens is to be politically informative and meaningful, individuals must encounter divergent perspectives and viewpoints. In this sense, disagreement must lie at the core of collective deliberation among citizens in democratic politics. We have argued that political disagreement is both widespread and persistent among citizens who communicate about politics.