Chapter 4 commences the empirical tests of our theory, beginning with Stage 1 of the 4D Framework: detection. We directly tackle a question buried implicitly in previous findings, as well as our own, that people prefer like-minded discussants: How do people detect the political views of others? The stakes of discussion may be higher in a polarized environment, but the readily available cues stemming from a divided and politicized society make the process of sorting into amicable discussions easier. We show that individuals are able to use a variety of cues to infer political leanings, including more obvious cues like demographic characteristics and extremely subtle cues, such as first names, pet preferences, and movie preferences. We then explore the existence of stereotypes that individuals hold about partisans, under the assumption that these attitudes could affect our ability to recognize others’ views and our willingness to engage in a discussion. We find that, consistent with research on affective polarization, individuals ascribe more negative personality traits to outpartisans and consider them to be ill-informed, ignorant, and overly reliant on partisan media.

Chapter 8 considers Stage 4 of the feedback loop: Determination. We examine how individuals anticipate relationships changing after political conversations and how discussion behavior is correlated with social distancing and social polarization. We use nationally representative survey data to capture individuals’ reflections on their own social distancing behaviors as well as their projections of such behavior onto hypothetical characters in vignette experiments. We uncover that about a quarter of Americans have distanced themselves socially from a friend because of politics. Americans have done so in a variety of ways, including stopping all political discussion, forbidding their children from playing together, and severing all social ties completely. Vignette experiments revealed that individuals are more likely to avoid future political and social interactions with others who disagree with them. Using data from the 2018 Cooperative Congressional Elections Project, we find that strong partisans in the most like-minded discussion networks were more likely to be socially polarized, compared to strong partisans who were in disagreeable discussion networks.

In this essay we review the recent history of “social sorting” in American politics. We describe how partisan identities have grown increasingly aligned with other social identities such as race, religion, ideological identity, region, and culture. We connect this phenomenon with research from social psychology and comparative politics on the psychological and sociological effects of this type of identity sorting. In particular, well-aligned identities increase intolerance of political and social outgroups, and societies politically divided along ethnic and/or religious lines are at greater risk of descending into civil war. In fact, early American political scientists suggested that the unique stability of American democracy lay in the cross-cutting (unaligned) nature of American political and social identities. We build on these theoretical connections with new findings from our own research on the depths of partisan animosity in the U.S. today. We find that Democrats and Republicans vilify their partisan opponents in the strongest terms, they feel less negatively when those opponents physically suffer, and a small minority advocate outright violence against them. We situate those modern hostilities in a broader American historical context. Finally, we discuss the normative implications of these findings. The obvious negative implications extend to the risk of widespread civil unrest and escalating political violence. One positive implication emerges, however. Under the current partisan alignment of racial and religious identities, the overwhelming divide between the parties is between traditionally high-status (e.g. white, Christian) and traditionally marginalized (e.g. non-white, non-Christian) groups. This provides unprecedented power to previously marginalized groups – an entire political party pressing for their advancement. The social unrest that we currently see can therefore either be seen as the path toward violent division, or as a step toward an inherently disruptive movement toward social justice.

This chapter unpacks and critically discusses the idea of democratic resilience vis-à-vis polarization that becomes “pernicious,” that is, it divides societies into mutually distrustful Us vs. Them camps. Democratic resilience, we argue, is a polity’s ability to produce electoral, programmatic, discursive, and organizational behavior that can jointly contain and reverse pernicious polarization and its democracy-eroding consequences. We apply comparative lessons to assess US resilience and vulnerability to such consequences, focusing on three factors: institutional constraints, formative rifts, and opposition capacities and strategies.