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

Whether political polarization is worse than in the past depends on how far back you look.

If your point of comparison is the mid-to-late 20th century, then yes—political polarization is significantly worse and is currently at its highest level in over a century. However, if you look back to the mid-19th century, today’s divisions, while severe, have not yet reached the ultimate crisis point of American history: the decade leading up to the U.S. Civil War.

To understand how today's polarization compares to the past, political scientists separate the issue into different eras and metrics.

1. The Legislative View: Polarization in Congress

To measure polarization among politicians, political scientists use DW-NOMINATE scores, which map lawmakers’ ideological positions based on their roll-call votes.

•The Mid-20th Century "Anomaly": From the 1940s through the 1970s, the U.S. experienced a historical anomaly of low polarization. The parties were highly overlapping. There were conservative Southern Democrats and liberal Northern Republicans. This meant bipartisanship was common, but it was also a product of a unique historical era.

•Today’s Great Divide: Starting in the late 1970s, the parties began to "sort". Today, the overlap has completely vanished. The most conservative Democrat in Congress is still more liberal than the most liberal Republican. According to DW-NOMINATE data, Congress is more polarized today than at any point since the Reconstruction Era (the late 1870s).

2. The Public View: "Affective" Polarization

We don't just disagree on policy anymore; we increasingly dislike each other. Political scientists call this affective polarization—the tendency of partisans to view the opposing party with active hostility and distrust.

•Skyrocketing Partisan Animosity: According to the Pew Research Center, the share of Americans with highly unfavorable views of the opposing party has more than doubled since the mid-1990s. By the 2020s, majorities on both sides (72% of Republicans and 63% of Democrats) viewed members of the other party not just as politically misguided, but as "more immoral" than other Americans.

•The Exceptionalism of the U.S.: A landmark study by researchers at Brown and Stanford universities found that while political polarization has risen globally, the United States has polarized faster and more deeply over the last 40 years than other major democracies (such as Canada, the UK, Germany, and Australia).

3. Comparing Today to the Civil War Era

The ultimate benchmark for American polarization is the 1850s and 1860s, and historians point out crucial differences between then and now:

•The Civil War Peak: In the 1850s, polarization was both "broad" and "deep." It was organized around a single, existential, and deeply moral issue: slavery. Because moral issues are incredibly difficult to compromise on, the system shattered. The country fractured geographically, leading to armed secession and a war that killed over 600,000 Americans.

•Today's Division: While modern political rhetoric is highly charged, historians emphasize that the U.S. is politically divided, but not militarily divided. There is no geographic line of secession, and our disputes—while intensely fought—remain largely within the bounds of civil, legal, and electoral institutions, even if those institutions are under immense strain.

4. What Makes Modern Polarization Unique?

While we are not in a civil war, today's polarization has features that make it feel uniquely intractable:

•The Rise of "Mega-Identities": In the past, a person's political party didn’t tell you much about their religion, where they lived, or their cultural tastes. Today, these identities have "sorted." Political affiliation has become a "mega-identity" that fuses race, geography (urban vs. rural), religion, and moral values. When you attack a political party today, voters feel you are attacking their entire way of life.

•The Media and Misperception: In the mid-20th century, most Americans got their news from three highly centralized TV networks. Today, the media ecosystem is highly fragmented. Partisan cable news, social media algorithms, and online echo chambers amplify the most extreme voices. Research shows that this leads to "phantom polarization," where average citizens assume ordinary voters on the other side are far more extreme and hostile than they actually are.

•Asymmetry: Studies of political trends note that polarization has not been entirely symmetrical. In Congress, the shift has been heavily driven by a pronounced rightward movement of the Republican party over the last few decades. Conversely, a 2026 Cambridge University study tracking public opinion found that since 2008, the American electorate’s polarization has been largely driven by the left-leaning public moving significantly further in a socially progressive direction, while the right-leaning public's social views remained relatively stable.

Summary

Is it worse than it's been in the past? Yes, for any period in living memory. You have to go back roughly 150 years to the Reconstruction era to find a time when political elites were this divided, and the rise of personal, identity-based "affective" hostility among everyday citizens is unprecedented in modern sociological tracking. However, keeping historical perspective is important: the country has survived deeper, more violent fractures in the past, most notably when the polarization of the 19th century pushed the nation into actual warfare.

Citations (12)

1usc.eduAcademic
usc.edu
Backs: “Whether political polarization is worse than in the past depends on how far back you look.”
2voteview.comAcademic
voteview.com
Backs: “If your point of comparison is the mid-to-late 20th century, then yes—political polarization is significantly worse and is currently at its highest level in over a century. However, if you look back to the mid-19th century, today’s divisions, while severe, have not yet reached the ultimate crisis point of American…”
3brookings.eduNonprofits and think tanks
brookings.edu
Backs: “However, if you look back to the mid-19th century, today’s divisions, while severe, have not yet reached the ultimate crisis point of American history: the decade leading up to the U.S. Civil War. To understand how today's polarization compares to the past, political scientists separate the issue into different eras…”
4thehilltoponline.comNews and media
thehilltoponline.com
Backs: “However, if you look back to the mid-19th century, today’s divisions, while severe, have not yet reached the ultimate crisis point of American history: the decade leading up to the U.S. Civil War. To understand how today's polarization compares to the past, political scientists separate the issue into different eras…”
5github.comForums and Q&A
github.com
Backs: “The Legislative View: Polarization in Congress. To measure polarization among politicians, political scientists use DW-NOMINATE scores, which map lawmakers’ ideological positions based on their roll-call votes. The Mid-20th Century "Anomaly": From the 1940s through the 1970s, the U.S.”
6pewresearch.orgNonprofits and think tanks
pewresearch.org
Backs: “The Legislative View: Polarization in Congress. To measure polarization among politicians, political scientists use DW-NOMINATE scores, which map lawmakers’ ideological positions based on their roll-call votes. The Mid-20th Century "Anomaly": From the 1940s through the 1970s, the U.S.”
7cpreview.orgNot yet classified
cpreview.org
Backs: “There were conservative Southern Democrats and liberal Northern Republicans. This meant bipartisanship was common, but it was also a product of a unique historical era.”
8brown.eduAcademic
brown.edu
Backs: “Political scientists call this affective polarization—the tendency of partisans to view the opposing party with active hostility and distrust. Skyrocketing Partisan Animosity: According to the Pew Research Center, the share of Americans with highly unfavorable views of the opposing party has more than doubled since…”
9wikipedia.orgEncyclopedias and referencequality 0.83
wikipedia.org
Backs: “Political scientists call this affective polarization—the tendency of partisans to view the opposing party with active hostility and distrust. Skyrocketing Partisan Animosity: According to the Pew Research Center, the share of Americans with highly unfavorable views of the opposing party has more than doubled since…”
10syr.eduAcademic
syr.edu
Backs: “By the 2020s, majorities on both sides (72% of Republicans and 63% of Democrats) viewed members of the other party not just as politically misguided, but as "more immoral" than other Americans. The Exceptionalism of the U.S.: A landmark study by researchers at Brown and Stanford universities found that while political…”
11cam.ac.ukAcademic
cam.ac.uk
Backs: “Today, these identities have "sorted." Political affiliation has become a "mega-identity" that fuses race, geography (urban vs.”
12nih.govGovernment
nih.gov
Backs: “Asymmetry: Studies of political trends note that polarization has not been entirely symmetrical. In Congress, the shift has been heavily driven by a pronounced rightward movement of the Republican party over the last few decades.”