Is political polarization worse than it's been in the past?
Most sources say polarization is at or near historic highs, while the USC piece (some political scientists), the Cambridge piece and the Nature study suggest it is not unprecedented, feels worse than it is, or has not grown for some groups.
Short answer: Yes, in most measurable ways—especially among political elites and in terms of partisan animosity—but the picture is nuanced depending on how you define "polarization" and what time period you compare to.
Where the evidence strongly supports "worse than before"
Congress/elites: A Pew Research Center analysis finds that, on average, Democrats and Republicans are farther apart ideologically today than at any time in the past 50 years. Both parties have grown more ideologically cohesive, with only about two dozen moderate Democrats and Republicans left on Capitol Hill, versus more than 160 in 1971-72.
Historical ideological-distance data (NOMINATE scores) show ideological distance between the parties began to grow during the 1970s to the extent that Congress is now more polarized than at any time since the late 1870s Reconstruction Era. The "overlap interval" — the number of legislators whose positions cross party lines — has shrunk to essentially zero today, whereas in the 1960s, for instance, you had intervals where about 50 percent of the legislators in the two parties overlapped.
Partisan identity/ideology among voters: Republicans have always been most likely to identify as conservative, but in 2024, 77% described themselves as such, marking a new high, while since 2012, liberal Democrats have far outpaced moderate Democrats, including in the past three years, when clear majorities have identified as liberal.
Affective polarization (dislike of the opposing party): a wide partisan gap in presidential approval has become the norm — in Economist/YouGov polls since 2009, partisan differences in approval ratings for Obama, Trump, and Biden have been 71, 74, and 71 points, respectively, and this gap has even spread to figures like First Ladies, with a 70-point gap in favorable opinion of Jill Biden between Republicans and Democrats, and a 76-point gap for Melania Trump. Compare that to the Bush era, when the gap in Democrats' and Republicans' approval of George H.W. Bush was 37 points, but for his son George W. Bush it had grown to a 68-point spread.
Important caveats and counter-evidence
Bottom line
By nearly every elite-level and partisan-identity metric political scientists track—congressional voting records, self-identified ideology, and especially cross-party animosity ("affective polarization")—polarization is at or near modern highs, with most trends tracing back to roughly the 1970s-1990s and accelerating since. However, some researchers caution that (a) this isn't unprecedented compared to extreme historical moments like the Civil War, and (b) ordinary Americans' actual policy views may be less starkly divided than the loudest voices and elite behavior suggest.
Citations (13)
- The polarization in today’s Congress has roots that go back decades
Source excerpt: “Indeed, a Pew Research Center analysis finds that, on average, Democrats and Republicans are farther apart ideologically today than at any ... # The ...”
evidence, article, points to yes. Claim: Pew finds Democrats and Republicans are farther apart ideologically today than at any time in the past 50 years.
- The polarization in today’s Congress has roots that go back decades
Source excerpt: “A line graph showing that Republicans have moved further to the right than Democrats have to the left - Both parties have grown more ideologically co...”
statistic, article, points to yes. Claim: Both parties have grown more cohesive, with only about two dozen moderates left in Congress versus more than 160 in 1971-72.
- Political polarization at its worst since the Civil War - USC Today
Source excerpt: “Following a period of a much more balanced Congress during the middle of the 20th century, ideological distance between the parties began to grow duri...”
evidence, article, points to yes. Claim: Ideological distance between parties began to grow in the 1970s; Congress is the most polarized since the late 1870s.
- Political polarization at its worst since the Civil War - USC Today
Source excerpt: “In the 1960s, for instance, you had intervals where about 50 percent of the legislators in the two parties overlapped. Some political scientists ha...”
attribution, article, points to no. Claim: Some political scientists say current polarization is not an alarming anomaly compared with the slavery and Civil War era.
- U.S. Political Parties Historically Polarized Ideologically
Source excerpt: “## Republicans’ and Democrats’ Ideology Is Most Extreme in 30 Years Republicans have always been most likely to identify as conservative, but in 2024,...”
statistic, article, points to yes. Claim: In 2024, 77% of Republicans described themselves as conservative, a new high.
- U.S. Political Parties Historically Polarized Ideologically
Source excerpt: “Since 2012, liberal Democrats have far outpaced moderate Democrats, including in the past three years, when clear majorities have identified as libera...”
statistic, article, points to yes. Claim: Since 2012, liberal Democrats have far outpaced moderate Democrats, with clear majorities liberal in the past three years.
- Polarization is getting worse: Few see shared values with those in the other party
Source excerpt: “Since then, a wide partisan gap in presidential approval has become the norm. In Economist/YouGov Polls conducted since 2009, the partisan differenc...”
statistic, article, points to yes. Claim: Partisan gaps in approval of Obama, Trump and Biden were 71, 74 and 71 points respectively.
- Polarization is getting worse: Few see shared values with those in the other party
Source excerpt: “The gap in favorable opinion of Jill Biden between Republicans and Democrats was 70 points: 76% among Democrats and 6% of Republicans. More than three...”
statistic, article, points to yes. Claim: There was a 70-point partisan gap in favorability of Jill Biden and a 76-point gap for Melania Trump.
- Polarization is getting worse: Few see shared values with those in the other party
Source excerpt: “But the partisan gap also affects others who are close to recent presidents, even ... # Polarization is getting worse: Few see shared values with tho...”
statistic, article, points to yes. Claim: Partisan approval gap grew from 37 points for George H.W. Bush to 68 points for George W. Bush.
- Political division in the US surged from 2008 onwards
Source excerpt: “However, De-Wit argues that polarisation in the US can feel much worse than it is. “Political groups have moved further apart in recent years, but the...”
attribution, article, points to no. Claim: Researcher argues polarization in the US can feel much worse than it is; divisions are still fuzzy.
- Political division in the US surged from 2008 onwards
Source excerpt: “Despite shifts in opinion, both left and right-leaning sides of the US population have stayed the same size since 1988, and the range of opinions with...”
evidence, article, points to no. Claim: Left and right-leaning groups have stayed the same size since 1988, with only the distance between them increasing.
- Are American voters really as polarized as they seem? Rice research suggests yes
Source excerpt: “Rice research suggests yes A new study of American voters by researchers at Rice University and Stanford University shows that while response rates to...”
evidence, article, points to yes. Claim: Declining survey response rates could inflate apparent polarization, yet researchers still conclude people are more polarized than ever.
- Charting multidimensional ideological polarization across demographic groups in the USA
Source excerpt: “We observe that income and especially racial groups align into parties, but their ideological distance has not increased over time.”
evidence, article, points to no. Claim: Income and racial groups align into parties, but their ideological distance has not increased over time.