'American' is the Eye of the Beholder: American Identity, Racial Sorting, and Affective Polarization among White Americans

White Americans are more affectively polarized today than at any point since at least the 1870s-and the trend shows no sign of abating any time soon. Recent work using the Common In-group Identity Model (CIIM) suggests that appealing to a super-ordinate identity-in this case, American national identity-holds the potential of bridging the social distance between partisans (Levendusky, Americans, not partisans: can priming American national identity reduce affective polarization? J Polit 80(1):59-70, 2018). However, CIIM assumes that the normative content-i.e. the norms and stereotypes-that people associate with being an American are the same across subordinate groups. Using the 2016 and 2020 American National Election Studies cross-sectional surveys, as well as the 2016-2020 ANES panel survey, we demonstrate three key findings. First, White Democrats and White Republicans have systematically different ideas about what attributes are essential to being a member of the national community. Second, the association between partisanship and these competing conceptions of American identity among White Americans has gotten stronger during the Trump Era, largely because of Democrats adopting a more racially inclusive conception of American identity. Lastly, appeals to American identity only dampen out-partisan animosity when the demographic composition of the opposing party matches their racialized conception of American identity. When there is a mismatch between people's racialized conception of American identity and the composition of the opposition party, American identity is associated with higher levels of partisan hostility.