Törnberg, P. (2022).
PNAS of the United States of America,
119(42).
Abstract
Politics has in recent decades entered an era of intense polarization. Explanations have implicated digital media, with the so-called echo chamber remaining a dominant causal hypothesis despite growing challenge by empirical evidence. This paper suggests that this mounting evidence provides not only reason to reject the echo chamber hypothesis but also the foundation for an alternative causal mechanism. To propose such a mechanism, the paper draws on the literatures on affective polarization, digital media, and opinion dynamics. From the affective polarization literature, we follow the move from seeing polarization as diverging issue positions to rooted in sorting: an alignment of differences which is effectively dividing the electorate into two increasingly homogeneous megaparties. To explain the rise in sorting, the paper draws on opinion dynamics and digital media research to present a model which essentially turns the echo chamber on its head: it is not isolation from opposing views that drives polarization but precisely the fact that digital media bring us to interact outside our local bubble. When individuals interact locally, the outcome is a stable plural patchwork of cross-cutting conflicts. By encouraging nonlocal interaction, digital media drive an alignment of conflicts along partisan lines, thus effacing the counterbalancing effects of local heterogeneity. The result is polarization, even if individual interaction leads to convergence. The model thus suggests that digital media polarize through partisan sorting, creating a maelstrom in which more and more identities, beliefs, and cultural preferences become drawn into an all-encompassing societal division.
Significance
Recent years have seen a rapid rise of affective polarization, characterized by intense negative feelings between partisan groups. This represents a severe societal risk, threatening democratic institutions and constituting a metacrisis, reducing our capacity to respond to pressing societal challenges such as climate change, pandemics, or rising inequality. This paper provides a causal mechanism to explain this rise in polarization, by identifying how digital media may drive a sorting of differences, which has been linked to a breakdown of social cohesion and rising affective polarization. By outlining a potential causal link between digital media and affective polarization, the paper suggests ways of designing digital media so as to reduce their negative consequences.
