Political polarization over factual beliefs

Recent decades have seen increasing levels of political polarization in both the United States and Western Europe. Whereas the literature has commonly distinguished between ideological polarization (i.e., citizens’ overall divergence and partisan alignment in political views) and affective polarization (i.e., citizens’ sympathy towards partisan in-groups and antagonism towards partisan out-groups), this chapter proposes that a third core pillar of polarization should be added to this taxonomy because citizens are divided not only in their attitudes and their feelings toward each other, but also in their factual perceptions of reality. For example, the vast majority (84%) of American citizens who identify as a Democrat accept the scientific consensus that climate change is caused by human activity, but less than half (43%) of Republicans share this position. Similar partisan differences exist in factual beliefs about key issues such as the size of the immigrant population, the level of income inequality, the division of the tax burden, and the magnitude of defense spending. Nearly any political attitude is likely to be accompanied by at least some factual assumptions, even if citizens are not quite sure about these beliefs or when they are not even consciously aware of them. This chapter argues that factual belief polarization may be viewed both as a consequence and a potential cause of other types of polarization. Although the empirical evidence for the latter is still rather limited and inconclusive, it is easy to imagine how partisan divides in factual perceptions could fuel ideological disagreements and political hostility.