Using American National Election Studies (NES) data from 1952 to 2008—a longer timespan than any analysis to date—we evaluate the leading claims about growing polarization along authoritarian/nonauthoritarian lines and the reasons for that growth. We find authoritarianism’s impact has grown for partisanship and voting but has been consistent for policy attitudes—usually present for "social" and defense issues, but less so for social welfare and foreign policy. This suggests that authoritarianism’s importance is related to strategic politicians advancing issues that touch on the authoritarian/nonauthoritarian divide, and varies across election years.