Political polarization

For the social psychology concept, see group polarization.

Political polarization (spelled polarisation in British English) is the divergence of political attitudes away from the center, towards ideological extremes.^[1][2][3]

Most discussions of polarization in political science consider polarization in the context of political parties and democratic systems of government. In two-party systems, political polarization usually embodies the tension of its binary political ideologies and partisan identities.^{[1][2][3][4][5]} However, some political scientists assert that contemporary polarization depends less on policy differences on a left and right scale but increasingly on other divisions such as religious against secular, nationalist against globalist, traditional against modern, or rural against urban.^[6] Polarization is associated with the process of politicization.^[7]

Scholars distinguish between ideological polarization (differences between the policy positions) and affective polarization (an emotional dislike and distrust of political out-groups).^[8]

Definitions and measurements

Political scientists typically distinguish between two levels of political polarization: elite and mass. "Elite polarization" focuses on the polarization of the political elites, like party organizers and elected officials. "Mass polarization" (or popular polarization) focuses on the polarization of the masses, most often the electorate or general public.^{[9][10][11][12]}

Elite polarization

 

Political polarization in the United States House of Representatives (DW-Nominate scores)

Elite polarization refers to polarization between the party-in-government and the party-in-opposition.^[2] Polarized political parties are internally cohesive, unified, programmatic, and ideologically distinct; they are typically found in a parliamentary system of democratic governance.^{[13][9][11][12]}

In a two-party system, a polarized legislature has two important characteristics: first, there is little-to-no ideological overlap between members of the two parties; and second, almost all conflict over legislation and policies is split across a broad ideological divide. This leads to a conflation of political parties and ideologies (i.e., Democrat and Republican become nearly perfect synonyms for liberal and conservative) and the collapse of an ideological center.^{[13][9][11][12]} However, using a cross-national design that covers 25 European countries, a recent study shows that it is not the number of parties itself, but the way a party interreacts with another that influences the magnitude and nature of affective polarization.^[14]

The vast majority of studies on elite polarization focus on legislative and deliberative bodies. For many years, political scientists measured polarization in the US by examining the ratings of party members published by interest groups, but now, most analyze roll-call voting patterns to investigate trends in party-line voting and party unity.^[3][9] Gentzkow, Shapiro, and Taddy used the text of the Congressional Record to document differences in speech patterns between Republicans and Democrats as a measure of polarization, finding a dramatic increase in polarized speech patterns starting in 1994.^[15]

Mass polarization

Mass polarization, or popular polarization, occurs when an electorate's attitudes towards political issues, policies, celebrated figures, or other citizens are neatly divided along party lines.^{[9][11][12][16]} At the extreme, each camp questions the moral legitimacy of the other, viewing the opposing camp and its policies as an existential threat to their way of life or the nation as a whole.^[17][18]

There are multiple types or measures of mass polarization. Ideological polarization refers to the extent to which the electorate has divergent beliefs on ideological issues (e.g., abortion or affirmative action) or beliefs that are consistently conservative or liberal across a range of issues (e.g., having a conservative position on both abortion and affirmative action even if those positions are not "extreme").^[19] Partisan sorting refers to the extent to which the electorate "sorts" or identifies with a party based on their ideological, racial, religious, gender, or other demographic characteristics.^[20][21] Affective polarization refers to the extent to which the electorate "dislikes" or "distrusts" those from other parties.^[22]

Political scientists who study mass polarization generally rely on data from opinion polls and election surveys. They look for trends in respondents' opinions on a given issue, their voting history, and their political ideology (conservative, liberal, moderate, etc.), and they try to relate those trends to respondents' party identification and other potentially polarizing factors (like geographic location or income bracket).^[1][10] Political scientists typically limit their inquiry to issues and questions that have been constant over time, in order to compare the present day to what the political climate has historically been.^[16] Some of recent studies also use decision-making games to measure the extent to which ingroup members discriminate outgroup members relative to their group members.^[14]

Recent academic work shows how intolerance affects polarization.^[23] Having systematically less tolerance at the ideological extremes can lead to polarization with opinions more polarized than identities. In contrast, intolerance among moderates helps cohesion.

Some political scientists argue that polarization requires divergence on a broad range of issues,^[1][3] while others argue that only a few issues are required.^[2][4][5]

Affective polarization

Affective polarization refers to the phenomenon where individuals' feelings and emotions towards members of their own political party or group become more positive, while their feelings towards members of the opposing party or group become more negative. This can lead to increased hostility and a lack of willingness to compromise or work together with people who hold different political views. This phenomenon can be seen in both online and offline settings, and has been on the rise in several countries in recent years.^[24] Indeed, using innovative experiments in 25 European countries, a recent study shows that the magnitude of affective polarization over parties is much stronger compared to divides over other attributes that constitute traditional cleavages, such as class, religion, and even nationality, confirming the primacy of "partyism" and its generalizability across democratic countries. However, this study shows that affective polarization in Europe is not primarily driven by out-group animus while it finds both in-group and out-group bias statistically significant.^[25]

Causes

There are various causes of political polarization and these include political parties, redistricting, the public's political ideology, the mass media, and political context.

Party polarization

Some scholars argue that diverging parties has been one of the major driving forces of polarization as policy platforms have become more distant. This theory is based on recent trends in the United States Congress, where the majority party prioritizes the positions that are most aligned with its party platform and political ideology.^[26] The adoption of more ideologically distinct positions by political parties can cause polarization among both elites and the electorate. For example, after the passage of the Voting Rights Act, the number of conservative Democrats in Congress decreased, while the number of conservative Republicans increased. Within the electorate during the 1970s, Southern Democrats shifted toward the Republican Party, showing polarization among both the elites and the electorate of both main parties.^[13][27][28] In this sense, political polarization could be a top-down process, in which elite polarization leads to—or at least precedes—popular polarization.^[29] However, polarization among elites does not necessarily produce polarization within the electorate, and polarized electoral choices can often reflect elite polarization rather than voters' preferences.^{[3][9][10][12][16]}

Political scientists have shown politicians have an incentive to advance and support polarized positions.^[30] These argue that during the early 1990s, the Republican Party used polarizing tactics to become the majority party in the United States House of Representatives—which political scientists Thomas E. Mann and Norman Ornstein refer to as Newt Gingrich's "guerrilla war."^[13] What political scientists have found is that moderates are less likely to run than are candidates who are in line with party doctrine, otherwise known as "party fit."^[31] Other theories state politicians who cater to more extreme groups within their party tend to be more successful, helping them stay in office while simultaneously pulling their constituency toward a polar extreme.^[32] A study by Nicholson (2012) found voters are more polarized by contentious statements from leaders of the opposing party than from the leaders of their own party. As a result, political leaders may be more likely to take polarized stances.^[33]

With regards to multiparty systems, Giovanni Sartori (1966, 1976) claims the splitting of ideologies in the public constituency causes further divides within the political parties of the countries. He theorizes that the extremism of public ideological movement is the basis for the creation of highly polarized multiparty systems. Sartori named this polarizing phenomenon polarized pluralism and claimed it would lead to further polarization in many opposing directions (as opposed to in simply two directions, as in a polarized two-party system) over policy issues.^[34][35][36] Polarization in multiparty systems can also be defined along two ideological extremes, like in the case of India in the 1970s. Ideological splits within a number of India's major parties resulted in two polarized coalitions on the right and left, each consisting of multiple political parties.^[37]

Political fund-raisers and donors can also exert significant influence and control over legislators. Party leaders are expected to be productive fund-raisers, in order to support the party's campaigns. After Citizens United v. Federal Election Commission, special interests in the U.S. were able to greatly impact elections through increased undisclosed spending, notably through Super political action committees. Some, such as Washington Post opinion writer Robert Kaiser, argued this allowed wealthy people, corporations, unions, and other groups to push the parties' policy platforms toward ideological extremes, resulting in a state of greater polarization.^[13][38] Other scholars, such as Raymond J. La Raja and David L. Wiltse, note that this does not necessarily hold true for mass donors to political campaigns. These scholars argue a single donor who is polarized and contributes large sums to a campaign does not seem to usually drive a politician toward political extremes.^[39][40]

The public

In democracies and other representative governments, citizens vote for the political actors who will represent them. Some scholars argue that political polarization reflects the public's ideology and voting preferences.^{[28][41][42][43]} Dixit and Weibull (2007) claim that political polarization is a natural and regular phenomenon. Party loyalism is a strong element of voters' thinking. Individuals who have higher political knowledge will not be influenced by anything a politician says. The polarization is merely a reflection of the party that the voter belongs to, and whichever direction it moves in.^[44] They argue that there is a link between public differences in ideology and the polarization of representatives, but that an increase in preference differences is usually temporary and ultimately results in compromise.^[45] Fernbach, Rogers, Fox and Sloman (2013) argue that it is a result of people having an exaggerated faith in their understanding of complex issues. Asking people to explain their policy preferences in detail typically resulted in more moderate views. Simply asking them to list the reasons for their preferences did not result in any such moderation.^[46]

Studies undertaken in the U.S. (2019) and the UK (2022) have found that political polarisation is generally less acute among the public than is portrayed in the media.^[47][48]

Morris P. Fiorina (2006, 2008) posits the hypothesis that polarization is a phenomenon which does not hold for the public, and instead is formulated by commentators to draw further division in government.^[3][49][50] Other studies indicate that cultural differences focusing on ideological movements and geographical polarization within the United States constituency is correlated with rises in overall political polarization between 1972 and 2004.^[4][51]

Religious, ethnic, and other cultural divides within the public have often influenced the emergence of polarization. According to Layman et al. (2005), the ideological split between U.S. Republicans and Democrats also crosses into the religious cultural divide. They claim that Democrats have generally become more moderate in religious views whereas Republicans have become more traditionalist. For example, political scientists have shown that in the United States, voters who identify as Republican are more likely to vote for a strongly evangelical candidate than Democratic voters.^[52] This correlates with the rise in polarization in the United States.^[53] Another theory contends that religion does not contribute to full-group polarization, but rather, coalition and party activist polarization causes party shifts toward a political extreme.^[54]

In some post-colonial countries, the public may be polarized along ethnic divides that remain from the colonial regime.^[55] In South Africa in the late 1980s, members of the conservative, pro-apartheid National Party were no longer supportive of apartheid, and, therefore, no longer ideologically aligned with their party. Dutch Afrikaners, white English, and native Africans split based on racial divisions, causing polarization along ethnic lines.^[56][57]

Economic inequality can also motivate the polarization of the public.^[58] For example, in post-World War I Germany, the Communist Workers Party, and the National Socialists, a fascist party, emerged as the dominant political ideologies and proposed to address Germany's economic problems in drastically different ways.^[34][35] In Venezuela, in the late 20th century, presidential candidate Hugo Chávez used economic inequality in the country to polarize voters, employing a popular and aggressive tone to gain popularity.^[59]

Redistricting

The impact of redistricting—potentially through gerrymandering or the manipulation of electoral borders to favor a political party—on political polarization in the United States has been found to be minimal in research by leading political scientists. The logic for this minimal effect is twofold: first, gerrymandering is typically accomplished by packing opposition voters into a minority of congressional districts in a region, while distributing the preferred party's voters over a majority of districts by a slimmer majority than otherwise would have existed. The result of this is that the number of competitive congressional districts would be expected to increase, and in competitive districts representatives have to compete with the other party for the median voter, who tends to be more ideologically moderate. Second, political polarization has also occurred in the Senate, which does not experience redistricting because Senators represent fixed geographical units, i.e. states.^[60][61] The argument that redistricting, through gerrymandering, would contribute to political polarization is based on the idea that new non-competitive districts created would lead to the election of extremist candidates representing the supermajority party, with no accountability to the voice of the minority. One difficulty in testing this hypothesis is to disentangle gerrymandering effects from natural geographical sorting through individuals moving to congressional districts with a similar ideological makeup to their own. Carson et al. (2007), has found that redistricting has contributed to the greater level of polarization in the House of Representatives than in the Senate, however that this effect has been "relatively modest".^[62] Politically motivated redistricting has been associated with the rise in partisanship in the U.S. House of Representatives between 1992 and 1994.^[63][64]

The media

The mass media has grown as an institution over the past half-century. Political scientists argue that this has particularly affected the voting public in the last three decades, as previously less partisan viewers are given more polarized news media choices. The mass media's current, fragmented, high-choice environment has induced a movement of the audience from more even-toned political programming to more antagonistic and one-sided broadcasts and articles. These programs tend to appeal to partisan viewers who watch the polarized programming as a self-confirming source for their ideologies.^[13][10][65]

Countries with less diversified but emerging media markets, such as China and South Korea, have become more polarized due to the diversification of political media.^[66][67] In addition, most search engines and social networks (e.g., Google, Facebook) now utilize computer algorithms as filters, which personalize web content based on a user's search history, location, and previous clicking patterns, creating more polarized access to information.^[68] This method of personalizing web content results in filter bubbles, a term coined by digital activist Eli Pariser that refers to the polarized ideological bubbles that are created by computer algorithms filtering out unrelated information and opposing views.^[69]

A 2011 study found ideological segregation of online news consumption is lower than the segregation of most offline news consumption and lower than the segregation of face-to-face interactions.^[70] This suggests that the filter bubbles effects of online media consumption are exaggerated. Other research also shows that online media does not contribute to the increased polarization of opinions.^[71] Solomon Messing and Sean J. Westwood state that individuals do not necessarily become polarized through media because they choose their own exposure, which tends to already align with their views.^[72] For instance, in an experiment where people could choose the content they wanted, people did not start to dislike their political opponents more after selecting between pro or anti immigration content.^[73] People did, however, start to counterargue the content.^[73]

Academic studies found that providing people with impartial, objective information has the potential to reduce political polarization, but the effect of information on polarization is highly sensitive to contextual factors.^[74] Specifically, polarization over government spending was reduced when people were provided with a "Taxpayer Receipt," but not when they were also asked how they wanted the money to be spent. This suggests that subtle factors like the mood and tone of partisan news sources may have a large effect on how the same information is interpreted. This is confirmed by another study that shows that different emotions of messages can lead to polarization or convergence: joy is prevalent in emotional polarization, while sadness and fear play significant roles in emotional convergence.^[75] These findings can help to design more socially responsible algorithms by starting to focus on the emotional content of algorithmic recommendations.

Research has primarily focused on the United States, a country with high polarization that has also increased over time. In Sweden, on the other hand, there is a stable ideological polarization over time.^[76] Experiments and surveys from Sweden also give limited support to the idea of increased ideological or affective polarization due to media use.^[77]

Further information: Social media § Political polarization, and Echo chamber (media)

The political context

Some of recent studies emphasize the role of electoral context and the way parties interact with each other. For example, a recent study shows that coalition partnership can moderate the extent of affective polarization over parties.^[78] However, this study does not find evidence that the number of political parties and district magnitude that captures the proportionality of electoral systems would influence the extent of affective polarization. Also, electoral context, such as electoral salience, involvement in elections, elite polarization, and the strength of Eurosceptic parties, can intensify the divide.^[14]

Consequences

The implications of political polarization "are not entirely clear and may include some benefits as well as detrimental consequences."^[79] Polarization can be benign, natural, and democratizing, or it can be pernicious, having long term malignant effects on society and congesting essential democratic functions.^[80] Where voters see the parties as less divergent, they are less likely to be satisfied with how their democracy works.^[81] While its exact effects are disputed, it clearly alters the political process and the political composition of the general public.^{[3][4][82][83]}

Pernicious polarization

In political science, pernicious polarization occurs when a single political cleavage overrides other divides and commonalities to the point it has boiled into a single divide which becomes entrenched and self-reinforcing.^[84] Unlike most types of polarization, pernicious polarization does not need to be ideological. Rather, pernicious polarization operates on a single political cleavage, which can be partisan identity, religious vs secular, globalist vs nationalist, urban vs rural, etc.^[85] This political divide creates an explosion of mutual group distrust which hardens between the two political parties (or coalitions) and spreads beyond the political sphere into societal relations.^[6] People begin to perceive politics as "us" vs "them."^[86] The office of Ombudsman of Argentina has been vacant since 2009, along with a companion Public Defender's office, allegedly because of pernicious polarization.^[87]

Causes

According to Carothers & O'Donohue (2019), pernicious polarization is a process most often driven by a single political cleavage dominating an otherwise pluralistic political life, overriding other cleavages.^[88] On the other hand, Slater & Arugay (2019) have argued that it's not the depth of a single social cleavage, but the political elite's process for removing a leader which best explains whether or not polarization truly becomes pernicious.^[89] Lebas & Munemo (2019) have argued pernicious polarization is marked by both deeper societal penetration and segregation than other forms of political polarization, making it less amenable to resolution.^[90] It is agreed, however, that pernicious polarization reinforces and entrenches itself, dragging the country into a downward spiral of anger and division for which there are no easy remedies.^[90][86]

Effect on governance

Pernicious polarization makes compromise, consensus, interaction, and tolerance increasingly costly and tenuous for individuals and political actors on both sides of the divide.^[91] Pernicious polarization routinely weakens respect for democratic norms, corrodes basic legislative processes, undermines the nonpartisan nature of the judiciary and fuels public disaffection with political parties. It exacerbates intolerance and discrimination, diminishes societal trust, and increases violence throughout the society. As well as potentially leading to democratic backsliding.^[88] In country-by-country instances of pernicious polarization, it is common to see the winner exclude the loser from positions of power or using means to prevent the loser from becoming a threat in the future. In these situations, the loser typically questions the legitimacy of the institutions allowing the winner to create a hegemony, which causes citizens to grow cynical towards politics. In these countries, politics is often seen as a self-referential power game that has nothing to do with people.^[92]

Effect on public trust

Perniciously polarized societies often witness public controversies over factually provable questions. During this process, facts and moral truths increasingly lose their weight, as more people conform to the messages of their own bloc. Social and political actors such as journalists, academics, and politicians either become engaged in partisan storytelling or else incur growing social, political, and economic costs. Electorates lose confidence in public institutions. Support for norms and democracy decline. It becomes increasingly difficult for people to act in a morally principled fashion by appealing to the truth or acting in line with one's values when it conflicts with one's party interests.^[91] Once pernicious polarization takes hold, it takes on a life of its own, regardless of earlier intentions.^[85]

Benefits of polarization

Several political scientists have argued that most types of political polarization are beneficial to democracy, as well as a natural feature. The simplifying features of polarization can help democratization. Strategies which depend on opposition and exclusion are present in all forms of observed politics.^[93] Political polarization can help transform or disrupt the status quo, sometimes addressing injustices or imbalances in a popular vs. oligarchic struggle.^[94][95]

Political polarization can serve to unify, invigorate, or mobilize potential allies at the elite and mass levels. It can also help to divide, weaken, or pacify competitors. Even the most celebrated social movements can be described as a "group of people involved in a conflict with clearly defined opponents having a conflictual orientation toward an opponent and a common identity."^[96]

Political polarization can also provide voting heuristics to help voters choose among candidates, enabling political parties to mobilize supporters and provide programmatic choices.^[97] Polarizing politics can also help to overcome internal differences and frame a common identity, based in part on a common opposition to those resisting reforms. Still, polarization can be a risky political tool even when intended as an instrument of democratization, as it risks turning pernicious and self-propagating.^[86]

US perspective

Main article: Political polarization in the United States

Global perspective

Outside of the U.S., there are plenty of modern-day examples of polarization in politics. A bulk of the research into global polarization comes from Europe. One example includes Pasokification in Greece. This is the trend from a shift from the center-left to a more far-left stance. Pasokification was caused by the Greek populous growing dissatisfied with the country's centrist more left-wing party and how they handled the Great Recession and the austerity measures the European Union put in place during recovery.^[98] Although the shift further to the left was a massive benefits to the liberal population in Greece, the results in Greece, as well as other nations like Germany, Sweden, and Italy, have not been able to sustain themselves. Parties who have made the shift left have recently shown a decline in the voting booths, evidence their supporters are uneasy of the future.^[99]

In the 2010s, the shift in Greece to the far left is similar to the shift in countries like Poland, France, and the UK to more far-right conservative positions. Much of the polarization in these nations leads to either a more socialist left-wing party, or more nationalist right-wing party. These more polarized parties grow from the discontent of more moderate parties inability to provide progressive changes in either direction. In Poland, France, and the UK, there is heavy anti-Islam sentiment and the rise of populist commentary. The general population of the right in these countries tends to hold onto these more aggressive stances and pulls the parties further to the right. These stances include populist messages with Islamophobic, isolationist, and anti-LGBTQ language.^[100][101]

Regarding the case of Brazil, some authors have questioned the use of the term. Rafael Poço and Rodrigo de Almeida coined the term "asymmetric polarization"^[102] to refer to the Brazilian general elections of 2022 that opposed a far-right candidate against a center-left. In a similar manner, Sergio Schargel and Guilherme Simões Reis suggests that polarization is not anti-democratic, but rather democracy in its essence. Furthermore, they also criticize how the concept has been used to falsely imply that a country is divided between two extremes: "rhetoric of polarization offers people the idea that choosing between democracy and authoritarianism, between a democratic center-left and a Brazilian version of fascism, is something to ponder — and that it is a difficult choice."^[103]

See also

• Civil war
• Contentious politics
• Cultural pluralism, in contrast
• Democratic backsliding
• False dilemma
• Hate speech
• Ideocracy
• Income inequality in the United States § Political polarization
• Left–right politics
• Moral foundations theory
• Multi-party system
• Partisan (political)
• Social polarization
• State collapse

References

1. DiMaggio, Paul; Evans, John; Bryson, Bethany (1 November 1996). (PDF). American Journal of Sociology. 102 (3): 690–755. doi:10.1086/230995. S2CID 144020785. Archived from the original (PDF) on 4 March 2016. Retrieved 22 April 2013.
2. Baldassarri, Delia; Gelman, Andrew (1 September 2008). "Partisans without Constraint: Political Polarization and Trends in American Public Opinion". American Journal of Sociology. 114 (2): 408–446. CiteSeerX 10.1.1.69.255. doi:10.1086/590649. S2CID 222436264.
3. Fiorina, Morris P.; Abrams, Samuel J. (1 June 2008). "Political Polarization in the American Public". Annual Review of Political Science. 11 (1): 563–588. doi:10.1146/annurev.polisci.11.053106.153836.
4. Abramowitz, Alan I.; Saunders, Kyle L. (27 March 2008). "Is Polarization a Myth?". The Journal of Politics. 70 (2): 542. doi:10.1017/S0022381608080493. S2CID 44020272.
5. Bafumi, Joseph; Shapiro, Robert Y. (27 January 2009). "A New Partisan Voter" (PDF). The Journal of Politics. 71 (1): 1. doi:10.1017/S0022381608090014. S2CID 154400302.
6. McCoy, Jennifer; Rahman, Tahmina; Somer, Murat (January 2018). "Polarization and the Global Crisis of Democracy: Common Patterns, Dynamics, and Pernicious Consequences for Democratic Polities". American Behavioral Scientist. 62 (1): 16–42. doi:10.1177/0002764218759576. ISSN 0002-7642.
7. Chinn, Sedona; Hart, P. Sol; Soroka, Stuart (February 2020). "Politicization and Polarization in Climate Change News Content, 1985-2017". Science Communication. 42 (1): 119–125. doi:10.1177/1075547019900290. S2CID 212781410.
8. Iyengar, Shanto; Lelkes, Yphtach; Levendusky, Matthew; Malhotra, Neil; Westwood, Sean J. (2019). "The Origins and Consequences of Affective Polarization in the United States". Annual Review of Political Science. 22 (1): 129–146. doi:10.1146/annurev-polisci-051117-073034. ISSN 1094-2939. S2CID 102523958.
9. McCarty, Nolan; Poole, Keith T.; Rosenthal, Howard (2006). Polarized America : the dance of ideology and unequal riches. MIT Press. Cambridge, Mass. ISBN 978-0262134644.
10. Hetherington, Marc J. (17 February 2009). "Review Article: Putting Polarization in Perspective". British Journal of Political Science. 39 (2): 413. doi:10.1017/S0007123408000501.
11. Layman, Geoffrey C.; Carsey, Thomas M.; Horowitz, Juliana Menasce (1 June 2006). "Party Polarization in American Politics: Characteristics, Causes, and Consequences". Annual Review of Political Science. 9 (1): 83–110. doi:10.1146/annurev.polisci.9.070204.105138.
12. Carmines, E. G.; Ensley, M.J.; Wagner, M.W. (23 October 2012). "Who Fits the Left–Right Divide? Partisan Polarization in the American Electorate". American Behavioral Scientist. 56 (12): 1631–1653. doi:10.1177/0002764212463353. S2CID 147108446.
13. Mann, Thomas E.; Ornstein, Norman J. (2012). . Basic Books. ISBN 978-0465031337. Archived from the original on 2014-07-05.
14. Hahm, Hyeonho; Hilpert, David; König, Thomas (2022-11-07). "Divided by Europe: affective polarisation in the context of European elections". West European Politics. 46 (4): 705–731. doi:10.1080/01402382.2022.2133277. ISSN 0140-2382. S2CID 253432411.
15. Gentzkow, Matthew, and Shapiro, Jesse, and Taddy, Matt Measuring Polarization in High-Dimensional Data: Method and Application to Congressional Speech"
16. Claassen, R.L.; Highton, B. (9 September 2008). "Policy Polarization among Party Elites and the Significance of Political Awareness in the Mass Public". Political Research Quarterly. 62 (3): 538–551. doi:10.1177/1065912908322415. S2CID 154392221.
17. "Partisanship and Political Animosity in 2016". Pew Research Center for the People and the Press. 2016-06-22. Retrieved 2019-10-26.
18. García-Guadilla, María Pilar; Mallen, Ana (2019-01-01). "Polarization, Participatory Democracy, and Democratic Erosion in Venezuela's Twenty-First Century Socialism". The Annals of the American Academy of Political and Social Science. 681 (1): 62–77. doi:10.1177/0002716218817733. ISSN 0002-7162. S2CID 149617060.
19. Abramowitz, Alan I.; Saunders, Kyle L. (2008). "Is Polarization a Myth?". The Journal of Politics. 70 (2): 542–555. doi:10.1017/s0022381608080493. ISSN 0022-3816. JSTOR 10.1017/s0022381608080493. S2CID 44020272.
20. Mason, Lilliana (2015). ""I Disrespectfully Agree": The Differential Effects of Partisan Sorting on Social and Issue Polarization". American Journal of Political Science. 59 (1): 128–145. doi:10.1111/ajps.12089. ISSN 0092-5853. JSTOR 24363600.
21. Mason, Lilliana; Wronski, Julie (2018). "One Tribe to Bind Them All: How Our Social Group Attachments Strengthen Partisanship". Political Psychology. 39 (S1): 257–277. doi:10.1111/pops.12485. ISSN 1467-9221.
22. Iyengar, Shanto; Lelkes, Yphtach; Levendusky, Matthew; Malhotra, Neil; Westwood, Sean J. (2019-05-11). "The Origins and Consequences of Affective Polarization in the United States". Annual Review of Political Science. 22 (1): 129–146. doi:10.1146/annurev-polisci-051117-073034. ISSN 1094-2939.
23. Genicot, Garance (2022). "Tolerance and Compromise in Social Networks". Journal of Political Economy. 130: 94–120. doi:10.1086/717041. S2CID 242818458. Retrieved 2021-01-29.
24. Boxell, Levi; Gentzkow, Matthew; Shapiro, Jesse M. (2022-01-25). "Cross-Country Trends in Affective Polarization". The Review of Economics and Statistics: 1–60. doi:10.1162/rest_a_01160. ISSN 0034-6535.
25. Hahm, Hyeonho; Hilpert, David; König, Thomas (2023-03-30). "Divided We Unite: The Nature of Partyism and the Role of Coalition Partnership in Europe". American Political Science Review: 1–19. doi:10.1017/S0003055423000266. ISSN 0003-0554. S2CID 257873474.
26. Ura, Joseph Daniel; Ellis, Christopher R. (10 February 2012). "Partisan Moods: Polarization and the Dynamics of Mass Party Preferences". The Journal of Politics. 74 (1): 277–291. doi:10.1017/S0022381611001587. hdl:1969.1/178724. S2CID 55325200.
27. Abramowitz, Alan I.; Saunders, Kyle L. (August 1998). "Ideological Realignment in the U.S. Electorate". The Journal of Politics. 60 (3): 634. doi:10.2307/2647642. JSTOR 2647642. S2CID 154980825.
28. Galston, William A. (2009). "Political Polarization and the U.S. Judiciary". UKMC Law Review. 77 (207).
29. Benkler, Yochai (2018). Network Propaganda: Manipulation, Disinformation, and Radicalization in American Politics. Oxford Scholarship Online (published 2018-10-01). doi:10.1093/oso/9780190923624.003.0010. ISBN 978-0-19-092366-2.
30. Beniers, Klaas J.; Dur, Robert (1 February 2007). "Politicians' motivation, political culture, and electoral competition" (PDF). International Tax and Public Finance. 14 (1): 29–54. doi:10.1007/s10797-006-8878-y. S2CID 39796862.
31. Thomsen, Danielle M. (2014). "Ideological Moderates Won't Run: How Party Fit Matters for Partisan Polarization in Congress". The Journal of Politics. 76 (3): 786–797. doi:10.1017/s0022381614000243. hdl:10161/8931. JSTOR 0022381614000243. S2CID 154980416.
32. Hirano, Shigeo Jr.; James M. Snyder; Michael M. Ting (2009). (PDF). Journal of Politics. 71 (4): 1467–1480. doi:10.1017/s0022381609990247. S2CID 11453544. Archived from the original (PDF) on 2014-05-31. Retrieved 2013-04-22.
33. Nicholson, Stephen P. (1 January 2012). "Polarizing Cues". American Journal of Political Science. 56 (1): 52–66. doi:10.1111/j.1540-5907.2011.00541.x. PMID 22400143. S2CID 147497906.
34. Sartori, Giovanni (1966). "European political parties: the case of polarized pluralism". Political Parties and Political Development: 137–176. doi:10.1515/9781400875337-006. ISBN 978-1400875337.
35. Sartori, Giovanni (1976). Parties and party systems : a framework for analysis ([Nouvelle édition] ed.). Colchester: ECPR. ISBN 978-0954796617.
36. Johnston, Richard (17 December 2008). "Polarized Pluralism in the Canadian Party System: Presidential Address to the Canadian Political Science Association, June 5, 2008". Canadian Journal of Political Science. 41 (4): 815. doi:10.1017/S0008423908081110. S2CID 154599342.
37. Davey, Hampton (1 August 1972). "Polarization and Consensus in Indian Party Politics". Asian Survey. 12 (8): 701–716. doi:10.2307/2643110. JSTOR 2643110.
38. Kaiser, Robert G. (2010). So damn much money : the triumph of lobbying and the corrosion of American government (1st Vintage Books ed.). New York: Vintage Books. ISBN 978-0307385888.
39. La Raja, R.J.; Wiltse, D.L. (13 December 2011). "Don't Blame Donors for Ideological Polarization of Political Parties: Ideological Change and Stability Among Political Contributors, 1972–2008". American Politics Research. 40 (3): 501–530. doi:10.1177/1532673X11429845. S2CID 143588919.
40. Tam Cho, Wendy K.; Gimpel, James G. (1 April 2007). "Prospecting for (Campaign) Gold" (PDF). American Journal of Political Science. 51 (2): 255–268. doi:10.1111/j.1540-5907.2007.00249.x.
41. Garner, Andrew; Palmer, Harvey (June 2011). "Polarization and issue consistency over time". Political Behavior. Springer. 33 (2): 225–246. doi:10.1007/s11109-010-9136-7. S2CID 143137236.
42. Mason, Lilliana (January 2013). "The rise of uncivil agreement: issue versus behavioral polarization in the American electorate". American Behavioral Scientist. SAGE. 57 (1): 140–159. doi:10.1177/0002764212463363. S2CID 147084342.
43. Murakami, Michael H. (2007). . Paper Presented at the Annual Meeting of the American Political Science Association, Hyatt Regency Chicago and the Sheraton Chicago Hotel and Towers, Chicago, Illinois. Archived from the original on 2015-04-03. Retrieved 2013-04-22.
44. Barber, Michael; Pope, Jeremy C. (February 2019). "Does Party Trump Ideology? Disentangling Party and Ideology in America". American Political Science Review. 113 (1): 38–54. doi:10.1017/S0003055418000795. S2CID 150286388.
45. Dixit, Avinash K.; Weibull, Jörgen W. (1 May 2007). "Political polarization". Proceedings of the National Academy of Sciences. National Academy of Sciences. 104 (18): 7351–7356. Bibcode:2007PNAS..104.7351D. doi:10.1073/pnas.0702071104. JSTOR 25427490. PMC 1863477. PMID 17452633.
46. Fernbach, Phillip; Rogers, Todd; Fox, Craig; Sloman, Steven (25 April 2013), "Political Extremism Is Supported by an Illusion of Understanding" (PDF), Psychological Science, 24 (6): 939–946, doi:10.1177/0956797612464058, PMID 23620547, S2CID 6173291
47. Stephen Hawkins, Daniel Yudkin, Tim Dixon (June 2019). "The Perception Gap". More in Common. Retrieved 11 May 2022.{{cite web}}: CS1 maint: multiple names: authors list (link)
48. Renie Anjeh, Isabel Doraisamy (April 2022). "The Centre holds". Global Future. Retrieved 11 May 2022.
49. Fiorina, Morris P.; Samuel A. Abrams; Jeremy C. Pope (2006). Culture War? The Myth of a Polarized America. Pearson Longman. ISBN 978-0321276407.
50. Born, Richard (February 1994). "[Split-ticket voters, divided government, and Fiorina's policy-balancing model]: rejoinder". Legislative Studies Quarterly. American Political Science Association. 19 (1): 126–129. doi:10.2307/439804. JSTOR 439804.
51. Abramowitz, Alan; Saunders, Kyle L. (July 2005). (PDF). The Forum. De Gruyter. 3 (2): 1–22. doi:10.2202/1540-8884.1076. S2CID 145471342. Archived from the original on 2013-10-19.{{cite journal}}: CS1 maint: bot: original URL status unknown (link)
52. Campbell, David E.; Green, John C.; Layman, Geoffrey C. (January 2011). "The party faithful: partisan images, candidate religion, and the electoral impact of party identification". American Journal of Political Science. Wiley. 55 (1): 42–58. doi:10.1111/j.1540-5907.2010.00474.x.
53. Layman, Geoffrey C.; Green, John C. (January 2006). "Wars and rumours of wars: the contexts of cultural conflict in American political behaviour". British Journal of Political Science. Cambridge Journals. 36 (1): 61–89. doi:10.1017/S0007123406000044. JSTOR 4092316. S2CID 144870729.
54. Brooks, Clem; Manza, Jeff (1 May 2004). (PDF). The Sociological Quarterly. Wiley. 45 (3): 421–450. doi:10.1111/j.1533-8525.2004.tb02297.x. S2CID 1887424. Archived from the original (PDF) on 11 June 2010. Retrieved 22 April 2013.
55. Bhavnani, Ravi; Miodownik, Dan (February 2009). "Ethnic polarization, ethnic salience, and Civil War". Journal of Conflict Resolution. SAGE. 53 (1): 30–49. doi:10.1177/0022002708325945. S2CID 145686111.
56. Sisk, Timothy D. (January 1989). "White politics in South Africa: politics under pressure". Africa Today. Indiana University Press. 36 (1): 29–39. JSTOR 4186531.
57. Darity, William A. (2009), "Economic theory and racial economic inequality", in Dodson, Howard; Palmer, Colin A. (eds.), The Black condition, East Lansing, Michigan: Michigan State University Press, pp. 1–43, ISBN 978-0870138386.
58. Stewart, Alexander J.; McCarty, Nolan; Bryson, Joanna J. (2020). "Polarization under rising inequality and economic decline". Science Advances. 6 (50). arXiv:1807.11477. Bibcode:2020SciA....6.4201S. doi:10.1126/sciadv.abd4201. PMC 7732181. PMID 33310855.
59. Márquez, Laureano; Eduardo, Sanabria (2018). "Llegó la dictablanda". Historieta de Venezuela: De Macuro a Maduro (1st ed.). Gráficas Pedrazas. p. 151. ISBN 978-1-7328777-1-9.
60. McCarty, Nolan; Poole, Keith T.; Rosenthal, Howard (1 July 2009). "Does Gerrymandering Cause Polarization?". American Journal of Political Science. 53 (3): 666–680. doi:10.1111/j.1540-5907.2009.00393.x.
61. Masket, Seth E.; Winburn, Jonathan; Wright, Gerald C. (4 January 2012). "The Gerrymanderers Are Coming! Legislative Redistricting Won't Affect Competition or Polarization Much, No Matter Who Does It" (PDF). PS: Political Science & Politics. 45 (1): 39–43. doi:10.1017/S1049096511001703. S2CID 45832354.
62. Carson, J.L.; Crespin, M.H.; Finocchiaro, C.J.; Rohde, D.W. (28 September 2007). "Redistricting and Party Polarization in the U.S. House of Representatives". American Politics Research. 35 (6): 878–904. doi:10.1177/1532673X07304263. S2CID 154527252.
63. McKee, SEth C. (March 2008). "The Effects of Redistricting on Voting Behavior in Incumbent U.S. House Elections, 1992–1994". Political Research Quarterly. 61 (1): 122–133. doi:10.1177/1065912907306473. S2CID 154836818. ProQuest 215329960.
64. Kousser, J (November 1996). "Estimating the Partisan Consequences of Redistricting Plans – Simply" (PDF). Legislative Studies Quarterly. 21 (4): 521–541. doi:10.2307/440460. JSTOR 440460. S2CID 153222480. ProQuest 60821189.
65. Hollander, B.A. (1 March 2008). "Tuning Out or Tuning Elsewhere? Partisanship, Polarization, and Media Migration from 1998 to 2006". Journalism & Mass Communication Quarterly. 85 (1): 23–40. doi:10.1177/107769900808500103. S2CID 144996244.
66. Yuan, Elaine Jingyan (2007). The New Multi-channel Media Environment in China: Diversity of Exposure in Television Viewing. Northwestern University. ISBN 978-1109940213.
67. Kim, S.J. (2011). Emerging patterns of news media use across multiple platforms and their political implications in south korea. Northwestern University. ProQuest 873972899.
68. Rushkoff, D. (2010). Program or be programmed: Ten commands for a digital age. Berkeley, CA: Soft Skull Press.
69. Pariser, E. (2011). The filter bubble: What the internet is hiding from you. New York, NY: The Penguin Press.
70. Gentzkow, Matthew; Shapiro, Jesse M. (2011-11-01). "Ideological Segregation Online and Offline *" (PDF). The Quarterly Journal of Economics. 126 (4): 1799–1839. doi:10.1093/qje/qjr044. hdl:1811/52901. ISSN 0033-5533. S2CID 9303073.
71. Hohenberg, Clemm von; Bernhard; Maes, Michael; Pradelski, Bary S.R. (2017-05-25). "Micro influence and macro dynamics of opinions". doi:10.2139/ssrn.2974413. S2CID 157851503. SSRN 2974413. {{cite journal}}: Cite journal requires |journal= (help)
72. Messing, Solomon; Westwood, Sean (31 Dec 2012). "Selective Exposure in the Age of Social Media". Communication Research. 41 (8): 1042–1063. doi:10.1177/0093650212466406. S2CID 35373607.
73. Dahlgren, Peter M. (2021). "Forced vs. Selective Exposure: Threatening Messages Lead to Anger but Not Dislike of Political Opponents". Journal of Media Psychology. doi:10.1027/1864-1105/a000302 (inactive 1 August 2023).{{cite journal}}: CS1 maint: DOI inactive as of August 2023 (link)
74. Duhaime, Erik; Apfelbaum, Evan (2017). "Can Information Decrease Political Polarization? Evidence From the U.S. Taxpayer Receipt". Social Psychological and Personality Science. 8 (7): 736. doi:10.1177/1948550616687126. S2CID 151758489.
75. Hilbert, M., Ahmed, S., Cho, J., Liu, B., & Luu, J. (2018). Communicating with Algorithms: A Transfer Entropy Analysis of Emotions-based Escapes from Online Echo Chambers. Communication Methods and Measures, 12(4), 260–275. https://doi.org/10.1080/19312458.2018.1479843 ; https://www.martinhilbert.net/communicating-with-algorithms/
76. Oscarsson, Henrik; Bergman, Torbjörn; Bergström, Annika; Hellström, Johan (2021). Demokratirådets rapport 2021: polarisering i Sverige. Stockholm: SNS. ISBN 978-9188637567.
77. Dahlgren, Peter M. (2020). Media Echo Chambers: Selective Exposure and Confirmation Bias in Media Use, and its Consequences for Political Polarization. Gothenburg: University of Gothenburg. ISBN 978-91-88212-95-5.
78. Hahm, Hyeonho; Hilpert, David; König, Thomas (2023-03-30). "Divided We Unite: The Nature of Partyism and the Role of Coalition Partnership in Europe". American Political Science Review: 1–19. doi:10.1017/S0003055423000266. ISSN 0003-0554. S2CID 257873474.
79. Epstein, Diana; John D. Graham (2007). "Polarized Politics and Policy Consequences" (PDF). RAND Corporation.
80. "Varieties of Democracy Report 2019" (PDF).
81. Ridge, Hannah M (2021-01-20). "Just like the others: Party differences, perception, and satisfaction with democracy". Party Politics. 28 (3): 419–430. doi:10.1177/1354068820985193. ISSN 1354-0688. S2CID 234162430.
82. Pietro S. Nivola & David W. Brady, ed. (2006). Red and blue nation? Volume One: characteristics and causes of America's polarized politics. Washington, DC: Brookings Institution. ISBN 978-0815760832.
83. Pietro S. Nivola & David W. Brady, ed. (2008). Red and blue nation? Volume Two: Consequences and Correction of America's Polarized Politics ([Online-Ausg.] ed.). Washington, DC: Brookings Institution. ISBN 978-0815760801.
84. McCoy, Jennifer; Rahman, Tahmina (2016-07-25). "Polarized Democracies in Comparative Perspective: Toward a Conceptual Framework". {{cite journal}}: Cite journal requires |journal= (help)
85. McCoy, Jennifer; Somer, Murat (2019-01-01). "Toward a Theory of Pernicious Polarization and How It Harms Democracies: Comparative Evidence and Possible Remedies". The Annals of the American Academy of Political and Social Science. 681 (1): 234–271. doi:10.1177/0002716218818782. ISSN 0002-7162. S2CID 150169330.
86. Somer, Murat; McCoy, Jennifer (2019-01-01). "Transformations through Polarizations and Global Threats to Democracy". The Annals of the American Academy of Political and Social Science. 681 (1): 8–22. doi:10.1177/0002716218818058. ISSN 0002-7162. S2CID 149764414.
87. Pablo Ezequiel Stropparo (2023). "Pueblo desnudo y público movilizado por el poder: Vacancia del Defensor del Pueblo: algunas transformaciones en la democracia y en la opinión pública en Argentina". Revista Mexicana de Opinión Pública (in Spanish). ISSN 1870-7300. Wikidata Q120637687.
88. and (2019-04-01). "Democracies Divided". Brookings. Retrieved 2019-11-24.
89. Arugay, Slater, Aires, Dan (2019). "Polarizing Figures: Executive Power and Institutional Conflict in Asian Democracies". American Behavioral Scientist. 62: 92–106. doi:10.1177/0002764218759577.{{cite journal}}: CS1 maint: multiple names: authors list (link)
90. LeBas, Adrienne; Munemo, Ngonidzashe (2019-01-01). "Elite Conflict, Compromise, and Enduring Authoritarianism: Polarization in Zimbabwe, 1980–2008". The Annals of the American Academy of Political and Social Science. 681 (1): 209–226. doi:10.1177/0002716218813897. ISSN 0002-7162. S2CID 150337601.
91. Somer, McCoy, Murat, Jennifer (2018). "Deja Vu? Polarization and Endangered Democracies in the 21st Century". American Behavioral Scientist. 62: 3–15. doi:10.1177/0002764218760371.{{cite journal}}: CS1 maint: multiple names: authors list (link)
92. Vegetti, Federico (2019-01-01). "The Political Nature of Ideological Polarization: The Case of Hungary". The Annals of the American Academy of Political and Social Science. 681 (1): 78–96. doi:10.1177/0002716218813895. ISSN 0002-7162. S2CID 199896426.
93. Schattschneider, E. E. (Elmer Eric) (1975). The semisovereign people: a realist's view of democracy in America. Boston, MA: Wadsworth Cengage Learning. ISBN 978-0030133664.
94. Stavrakakis, Yannis (January 2018). "Paradoxes of Polarization: Democracy's Inherent Division and the (Anti-) Populist Challenge". American Behavioral Scientist. 62 (1): 43–58. doi:10.1177/0002764218756924. ISSN 0002-7642.
95. Slater, Dan (2013). Diamond, Larry; Kapstein, Ethan B.; Converse, Nathan; Mattlin, Mikael; Phongpaichit, Pasuk; Baker, Chris (eds.). "Democratic Careening". World Politics. 65 (4): 729–763. doi:10.1017/S0043887113000233. ISSN 0043-8871. JSTOR 42002228. S2CID 201767801.
96. Kriesi, Hanspeter (2017). "16. Social movements". In Caramani, Daniele (ed.). Comparative Politics (4th ed.). Oxford University Press. doi:10.1093/hepl/9780198737421.003.0018. ISBN 978-0191851018.
97. Campbell, James E. (2016). Polarized. Princeton University Press. ISBN 978-0691172163.
98. Blackwater, Bill (Summer 2016). "Morality and left-wing politics: a case study of Jeremy Corbyn's Labour Party". Renewal. 24 – via Gale Literature Resource Center.
99. Eaton, George (2018). "Corbynism 2.0". New Statesman. 147.
100. Zarkov, Dubravka (2017-06-16). "Populism, polarization and social justice activism". European Journal of Women's Studies. 24 (3): 197–201. doi:10.1177/1350506817713439. ISSN 1350-5068.
101. Palonen, Emilia (2009). "Political Polarisation and Populism in Contemporary Hungary". Parliamentary Affairs. 62 (2): 318–334. doi:10.1093/pa/gsn048 – via Electronic Journal Center.
102. Poço e Almeida, Rafael e Rodrigo (30 January 2021). "Polarização em 2022 e a assimetria que poucos enxergam".
103. Schargel and Reis, Sergio e Guilherme (8 February 2023). "LANGUAGE AROUND BRAZIL'S ELECTION OBSCURES A DANGEROUS TREND". Inkstick.

Further reading

• Abramowitz, Alan (1994). "Issue Evolution Reconsidered: Racial Attitudes and Partisanship in the U.S. Electorate". The Sociological Quarterly. 38 (1): 1–24. doi:10.2307/2111333. JSTOR 2111333.
• Clark, Cal; Tan, Alexander C. (2012). "Political Polarization in Taiwan: A Growing Challenge to Catch-all Parties?" (PDF). Journal of Current Chinese Affairs. 41 (3): 7–31. doi:10.1177/186810261204100302. S2CID 73640516.
• Frymer, Paul. "Debating the Causes of Party Polarization in America". The Brennan Center Jorde Symposium on Constitutional Law. 2011: 335–350.
• Hahm, Hyeonho, David Hilpert and Thomas König (2023) "Divided We Unite: The Nature of Partyism and the Role of Coalition Partnership in Europe". American Political Science Review, DOI: 10.1017/S0003055423000266
• Hahm, Hyeonho, David Hilpert and Thomas König (2022) "Divided by Europe: Affective Polarisation in the Context of European Elections". West European Politics, DOI: 10.1080/01402382.2022.2133277
• Kallis, Aristotle A. Fascist ideology: territory and expansionism in Italy and Germany, 1922–1945. London, England; New York: Routledge, 2000.
• Keefer, Philip; Knack, Stephen (2002). "Polarization, Politics and Property Rights: Links between Inequality and Growth". Public Choice. 111 (1/2): 127–154. doi:10.1023/A:1015168000336. JSTOR 30026274. S2CID 9467286.
• Leege, David C., Kenneth D. Wald, Brian S. Krueger, and Paul D. Mueller. The Politics of Cultural Differences: Social Change and Voter Mobilization Strategies in the Post-New Deal Period. N.p.: University of Florida, 2001.
• McCarty, Nolan M. "Limits of Electoral and Legislative Reform in Addressing Polarization". The Brennan Center Jorde Symposium on Constitutional Law. 359: 359–372.
• Nivola, Peter. "Thinking About Political Polarization." The Brookings Institution, January 2005.
• Pierson, Paul and Eric Schickler. 2020. "Madison's Constitution Under Stress: A Developmental Analysis of Political Polarization." Annual Review of Political Science 23:1, 37-58
• Simon, Sheldon W. (1979). "China, Vietnam, and ASEAN: The Politics of Polarization". Asian Survey. 19 (12): 1171–1188. doi:10.2307/2643963. JSTOR 2643963.
• Pew Research Center, Political Polarization in the American Public, June 12, 2014, people-press.org.
• Stewart, Alexander J.; McCarty, Nolan; Bryson, Joanna J. (2020). "Polarization under rising inequality and economic decline". Science Advances. 6 (50): eabd4201. arXiv:1807.11477. Bibcode:2020SciA....6.4201S. doi:10.1126/sciadv.abd4201. PMC 7732181. PMID 33310855. S2CID 216144890.
• Sunstein, Cass R (2001). "Deliberative Trouble – Why Groups Go to Extremes". Yale Law Journal. 110 (71): 71–120. doi:10.2307/797587. JSTOR 797587.