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

Yes — by most measures, political polarization today is worse than it's been in generations, especially in the U.S.

Here's what the data shows across different dimensions:

Ideological Polarization (Policy Positions)

Congress is more divided than at any point in modern history. DW-NOMINATE scores reveal that in the periods during and immediately after World War II, the difference in ideology between the median Democrat and the median Republican in Congress did not differ nearly as much as they do today. Back then, Democrats were, on average, modestly left of center, and Republicans were, on average, modestly right of center.

The result is a near-total disappearance of ideological overlap between the parties: whereas there used to be many Republicans who were less conservative than the most conservative Democrat, and vice versa, there is no overlap today — the most liberal Republican is still more conservative than the most conservative Democrat. Pew Research has found similarly that Democrats and Republicans are more ideologically apart than they have been at any time in the past fifty years.

This divergence is also asymmetric. Polarization among U.S. legislators is asymmetric, as it has primarily been driven by a rightward shift among Republicans in Congress.

Affective Polarization (Dislike of the Other Side)

Even more striking is how much Americans dislike the opposing party now compared to the past. In the early 1980s, people typically gave their own party about 75 out of 100 and the other party around 45 out of 100 on favorability scales — that gap has grown substantially since.

Presidential approval is a clear example: in the spring before Harry Truman ran for a full term in 1948, two-thirds of Democrats (68%) and even half of Republicans (50%) approved of his job performance. By the time of Richard Nixon, the gap between his party's approval and the opposition party's grew to 47 points. By Barack Obama's time, it expanded to 72 points.

Mass Public Polarization

The share of ideologically "pure" partisans has also grown. The overall share of Americans who express consistently conservative or consistently liberal opinions has doubled over the past two decades from 10% to 21%. At the same time, ideological thinking is now much more closely aligned with partisanship than in the past — as a result, ideological overlap between the two parties has diminished: today, 92% of Republicans are to the right of the median Democrat, and 94% of Democrats are to the left of the median Republican.

Global Context

This isn't just a U.S. phenomenon, though the U.S. stands out. In the late 20th and early 21st century, the U.S. has experienced a greater surge in ideological polarization and affective polarization than comparable democracies. Globally, polarization indices suggest we may be near historic highs: the global population-weighted V-Dem Political Polarization Index reached its highest level since 1946 in 2025, standing at 0.90.

Interestingly, one long-run index tracking the U.S. specifically going back to 1900 suggests the lowest level of political polarization in United States was recorded in 1949, with a value of -1.54, while the highest score was observed in 2025, when it reached 2.30 — essentially confirming current polarization sits at a century-long peak.

The Caveat

Not everyone agrees the public itself is as divided as the rhetoric suggests. Research cited by Carnegie notes that "preliminary research and polling that we have supported suggest that the population at large is less polarized than our political leaders." This points to an important distinction: elite polarization (among politicians and media figures) appears to be rising faster and further than polarization among ordinary citizens, many of whom remain more moderate than the discourse implies.

Bottom line: By nearly every standard metric — congressional voting records, partisan favorability ratings, ideological consistency, and cross-national indices — polarization today is at or near its highest point in at least 70-100 years. The main nuance is that this is more pronounced among political elites than the general public, and it's a largely asymmetric phenomenon driven more by rightward movement among Republicans than leftward movement among Democrats.