Affective polarization in US politics has surged, driven by core value differences rather than issues or partisanship.

Findings:

* Core value extremity significantly fuels disdain for the out-party and its candidates.

* This effect holds independent of issue attitude extremity or partisan/ideological identification strength.

Data & Methods:

* Analysis of ANES data spanning 1988-2016 reveals this connection in cross-sectional studies.

* Panel data from 1992-1996 demonstrates that past value extremity predicts future increased polarization.

Why It Matters:

These results highlight core values as a fundamental driver of political division.