Is political polarization worse than it's been in the past?

To answer whether political polarization is worse than in the past, political scientists and historians generally split the question into two parts: where we stand compared to modern living memory (the last 50 to 70 years) and where we stand compared to the entire span of American history (specifically the 19th century).

By almost every modern metric, political polarization in the United States is significantly worse than it has been in generations. However, it is not the worst it has ever been; that title belongs to the era of the American Civil War.

To understand how today’s polarization compares to the past, it helps to look at the three different ways researchers measure it: elite polarization (politicians), affective polarization (how voters feel), and ideological polarization (what voters actually believe).

1. Elite Polarization (The Divide in Congress)

Political scientists track the voting records of members of Congress using a metric called DW-NOMINATE scores, which place politicians on a liberal-to-conservative scale.

During the mid-20th century (the 1940s through the 1970s), there was massive ideological overlap between the two parties. Conservative Southern Democrats often voted with Northern Republicans, and moderate Northeastern Republicans often voted with Democrats. Today, that overlap has completely vanished.

The ideological gap between the median Democrat and the median Republican in Congress is wider now than at any point since the Reconstruction Era following the Civil War. Moderates have virtually disappeared from both congressional delegations, resulting in systemic gridlock and a breakdown of legislative compromise.

2. Affective Polarization (Hostility Between Voters)

Affective polarization refers to how much members of one political party dislike and distrust members of the opposing party.

Data from the Pew Research Center highlights how sharply this animosity has spiked: in 2016, 47% of Republicans and 35% of Democrats viewed the opposing party as "more immoral" than other Americans. By 2022, those numbers had jumped to 72% of Republicans and 63% of Democrats.

Furthermore, a study by economists at Brown and Stanford universities found that the U.S. is an outlier in this regard. While some European democracies have seen stable or even declining levels of partisan hostility, affective polarization in the U.S. has risen faster over the last 40 years than in any other comparable democracy (including Canada, the UK, Germany, and Australia).

3. Ideological Polarization & Partisan "Sorting"

For a long time, political scientists argued that while politicians were polarizing, everyday Americans were mostly moderate. They argued that voters were simply "sorting"—meaning that conservative Democrats became Republicans, and liberal Republicans became Democrats, leaving the actual beliefs of the average voter relatively unchanged.

However, more recent research indicates that actual ideological divisions are expanding. A study by the University of Cambridge's Political Psychology Lab tracked American political opinions over nearly four decades. It found that divisions on major social and political issues (like immigration, abortion, and systemic equality) increased by 64%, with almost all of that divergence occurring after 2008.

Interestingly, the study noted that this shift has been asymmetric: the American left has moved significantly further to the left on social issues (about 31.5% more socially liberal), while the average conservative's views on those same issues have remained relatively stable over the last 35 years.

Putting It in Historical Context

To understand if today is "the worst," we have to look at past peaks of division:

Summary

If you compare today to the mid-20th century, political polarization is vastly worse, more personal, and more structurally damaging to government functionality. If you compare today to the entirety of U.S. history, we are living through a period of division that rivals the gridlock and hostility of the Gilded Age, though we still remain short of the existential breaking point of the Civil War.