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

Yes—by most empirical measures, political polarization in the U.S. today is worse than at any point in the past several decades, though historians caution it still doesn't rival the most extreme periods in American history, like the Civil War era.

The case that it's historically severe (in recent memory)

In Congress: 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. This divide has roots going back decades: following a period of a much more balanced Congress during the middle of the 20th century, 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.

One striking measure is the "overlap interval"—how many members of one party are more moderate than members of the other. this measure shows how many Republicans lie to the right of the most right-leaning Democrat and how many Democrats lie to the left of the most left-leaning Republicans. Today, the overlap interval is zero. That's a dramatic shift: this was certainly not always true—in the 1960s, you had intervals where about 50 percent of the legislators in the two parties overlapped. Similarly, 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. The ranks of moderates have thinned dramatically too: there are now only about two dozen moderate Democrats and Republicans left on Capitol Hill, versus more than 160 in 1971-72.

Among the public: Pew's landmark research found that Republicans and Democrats are more divided along ideological lines – and partisan antipathy is deeper and more extensive – than at any point in recent history. Specifically, the overall share of Americans who express consistently conservative or consistently liberal opinions has doubled over the past two decades from 10% to 21%. Partisan dislike has also grown sharply: partisan animosity has increased substantially over the same period, with the share holding a highly negative view of the opposing party more than doubling since 1994. This trend has continued, as members of both parties who have unfavorable opinions of the opposing party doubled between 1994 and 2014, while those who have very unfavorable opinions of the opposing party are at record highs as of 2022.

A 2026 study using algorithmic opinion tracking found that the US left was 31.5% more socially liberal in 2024 compared to 1988, while the US right was only 2.8% more conservative—suggesting polarization has been driven disproportionately by one side's movement. The same study noted this polarization may have begun to level off during Biden's term, although it remains far higher than in previous decades. Researchers also point to tighter "sorting" between ideology and party label: "In the past, someone with left-wing views on one issue might have held right-wing views on another. That's rarer now," as one researcher put it, with elites sending clearer signals about which positions "go together."

The historical counterargument

Several scholars push back on the "worst ever" framing. A Civil War historian argues that current divisions pale in comparison to those of the mid-19th century. The scale of violence then dwarfs anything today: four years of civil war produced at least 620,000 military deaths—the equivalent of approximately 6.5 million dead in the United States of 2020. And on substance, no political issue in 2020 approaches slavery in the mid-19th century in terms of potential divisiveness.

A Columbia Political Review piece makes a similar point, noting the United States has had multiple periods of division before—in some cases, significantly worse than what we have right now, citing the early republic's Federalist-Anti-Federalist split (so severe that by 1804, New England Federalists were contemplating secession), the Civil War/Reconstruction era, and the Civil Rights era.

Other analysts note a subtler point: even though parties have moved apart, the public itself may not be as cleanly split as it seems. One researcher argued that polarization in the US can feel much worse than it is, because political groups have moved further apart in recent years, but these divisions are still fuzzy, and Americans are not split into entirely opposing camps.

Bottom line

If you're asking about the modern era (last 50-150 years) and looking at measurable indicators—congressional voting patterns, partisan animosity, ideological sorting—the data strongly support that polarization is at or near historic highs for that timeframe. But if you widen the lens to all of American history, periods like the Civil War, Reconstruction, and the early republic's partisan battles involved far more extreme division, including actual warfare, secession threats, and violence that make today's polarization look comparatively mild—even if it's still a serious and growing problem by recent historical standards.