Disagreement Does Not Always Mean Division: Evidence from Five Decades of American Public Opinion

Are those things on which Americans most disagree the same things that divide liberals and conservatives or Democrats and Republicans? How has this changed over time? To answer these questions, I use 350 subjective items from five decades of the General Social Survey. Estimating disagreement with ordinal dispersion and using a novel measure of sorting by party and ideological identification, I find an increasing positive association between the two phenomena. In the 1970s, the likelihood that opinion on contentious items divided partisans was low. Since then, this probability has increased. Disagreement has been more consistently associated with higher levels of ideological sorting, though this relationship has also strengthened since the 1980s. I then ask which items and substantive domains have propelled the politicization of disagreement. I decompose the estimated coefficients between disagreement and sorting by item to quantify their contribution in each decade. I find that opinions from two domains play a large role throughout the period: public spending, and sexuality and abortion. Nevertheless, there is a great deal of heterogeneity within domains and over time. Though disagreement between Americans has increasingly sorted, a relatively small number of items drive this relationship in any one decade. Even among voters, a good proportion of disagreement remains unrelated to ideological or partisan divisions.