Political polarization in the United States

Polarization is a historically common feature in American politics. Common scholarly questions include how the magnitude of modern polarization compares to various points in the past, and the extent to which polarization is a feature of American politics.[1]

Definition

Polarization has been defined as both a process and a state of being. A defining aspect of polarization, though not its only facet, is a bimodal distribution around conflicting points of view or philosophies. In general, defining a threshold at which an issue is "polarized" is imprecise; detecting the trend of polarization, however, (increasing, decreasing, or stable) is more straight-forward.[2]

A related concept is that of party homogeneity, which describes the similarities of the constituencies of two officials of the same party. There is also party polarization, which refers to the gap between the typical constituency of one party as compared to the other in a two-party system.[3]

History

Gilded Age

The Gilded Age of the late 19th century (c. 1870 – 1900) is considered to be one of the most politically polarized periods in American history, with open political violence and highly polarized political discourse.[4] A key event during this era was the election of 1896, which some scholars say led to an era of one-party rule, created "safe seats" for elected officials to build careers as politicians, increased party homogeneity, and increased party polarization. Political polarization was overall heightened, with Republicans strengthening their hold on industrial areas, and Democrats losing ground in the North and upper Midwest.[3]

1950s and 1960s

The 1950s and 1960s were marked by high levels of political bipartisanship, the results of a post-World War II "consensus" in American politics, as well as ideological diversity within each of the two major parties.[5]

1990 – present

Media and political figures began espousing the narrative of polarization in the early 1990s, with a notable example Pat Buchanan's speech at the 1992 Republican National Convention. In the speech, he declared a culture war for the future of the country. In 1994, the Democratic Party lost control of the House of Representatives for the first time in forty years. The narrative of political polarization became a recurring theme in the elections of 2000 and 2004. After George W. Bush was reelected in 2004, English historian Simon Schama noted that the US had not been so polarized since the American Civil War, and that a more apt name might be the Divided States of America.[2] From 1994 to 2014, the share of Americans who expressed either "consistently liberal" or "consistently conservative" opinions doubled from 10% to 21%. In 1994, the average Republican was more conservative than 70% of Democrats, compared to more conservative than 94% of Democrats in 2014. The average Democrat went from more liberal than 64% of Republicans to more liberal than 92% of Republicans during the same era.[6]

Potential causes

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.[7] 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.[8][9][10]

Political scientists have shown politicians have an incentive to advance and support polarized positions.[11] 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."[8] 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."[12] 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.[13] 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.[14]

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.[8][15] 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.[16][17]

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.[10][18][19][20] Dixit and Weibull (2007) claim that political polarization is a natural and regular phenomenon. 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.[21] 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.[22]

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.[2][23][24] 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.[25][26]

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.[27] This correlates with the rise in polarization in the United States.[28] 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.[29]

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.[30][31] 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".[32] Politically motivated redistricting has been associated with the rise in partisanship in the U.S. House of Representatives between 1992 and 1994.[33][34]

Media

A 2013 review concluded that there is no firm evidence that media institutions are contributing to the polarization of average Americans. No evidence supports the idea that longstanding news outlets are becoming increasingly partisan. Analyses confirm that the tone of evening news broadcasts remained unchanged from 1968 to 1996: largely centrist, with a small but constant bias towards Democratic Party positions. However, more partisan media pockets have emerged in blogs, talk radio, websites, and cable news channels, which are much more likely to use insulting language, mockery, and extremely dramatic reactions, collectively referred to as "outrage".[35]

Effects

Political violence

Some authors have found a correlation between polarization of political discourse and the prevalence of political violence.[4]

Trust in science

See also: Denialism

The General Social Survey periodically asks Americans whether they trust scientists. The proportion of American conservatives who say they place "a great deal of trust" in scientists fell from 48% in 1974 to 35% in 2010[36] and rose again to 39% in 2018.[37] Liberals and independents, meanwhile, report different levels of trust in science.

Congress

Political polarization among elites is negatively correlated with legislative efficiency, which is defined by the total number of laws passed, as well as the number of "major enactments" and "key votes". Evidence suggests that polarization of political elites may more strongly affect efficiency than polarization of Congress itself, with authors hypothesizing that the personal relationships among members of Congress may enable them to reach compromises on polarized legislation, though not if political elites allow no leeway for such.[4]

Negative effects of polarization on the United States Congress include increased gridlock and partisanship at the cost of quality and quantity of passed legislation.[38][39][40][41][42] It also incentivizes stall tactics and closed rules, such as filibusters on non-contentious issues and excluding minority party members from committee deliberations.[8][38][43] These strategies hamper transparency, oversight, and the government's ability to handle long-term domestic issues, especially those regarding the distribution of benefits.[39] Further, they foster animosity, as majority parties lose bipartisan and legislative coordination trying to expedite legislation to overcome them.[8][42]

Some scholars claim that political polarization is not so pervasive or destructive in influence, contending that partisan agreement is the historical trend in Congress and still frequent in the modern era, including on bills of political importance.[44][45][46] Some studies have found approximately 80% of House bills passed in the modern era to have had support from both parties.[44]

The public

Opinions on polarization's effects on the public are mixed. Some argue that the growing polarization in government has directly contributed to political polarization in the electorate,[47] but this is not unanimous.[44][48]

Some scholars argue that polarization lowers public interest in politics, party identification and voter turnout.[47] It encourages confrontational dynamics between parties that can lower overall public trust and approval in government.,[49] and causes the public to perceive the general political debate as less civil,[47][39] which can alienate voters. More polarized candidates, especially when voters aren't aware of the increase, also tend to be less representative of the public's wishes.[47][39][49]

On the other hand, others assert that elite polarization has galvanized the public's political participation in the United States, citing greater voting and nonvoting participation, engagement and investment in campaigns, and increased positive attitude toward government responsiveness.[49][50] Polarized parties become more ideologically unified, furthering voter knowledge about their positions and increasing their standard to similarly-aligned voters.[47][50]

The media

As Mann and Ornstein argue, political polarization and the proliferation of media sources have "reinforce[d] tribal divisions, while enhancing a climate where facts are no longer driving the debate and deliberation, nor are they shared by the larger public."[8] As other scholars have argued, the media often support and provoke the stall and closed rules tactics that disrupt regular policy procedure.[8][51]

While the media are not immune to general public opinion and reduced polarization allows them to appeal to a larger audience,[52] polarized environments make it easier for the media and interest groups to hold elected officials more accountable for their policy promises and positions,[38][51] generally healthy for democracy.[38]

Judicial systems

Judicial systems can also be affected by the implications of political polarization. For the United States, in particular, polarization lowers confirmation rates of judges;[43] In 2012, the confirmation rate of presidential circuit court appointments was approximately 50% as opposed to the above 90% rate in the late 1970s and early 1980s.[8] More polarized parties have more aggressively blocked nominees and used tactics to hinder executive agendas.[43][53] Political scientist Sarah Binder (2000) argues that "senatorial intolerance for the opposing party’s nominees is itself a function of polarization."[43] Negative consequences of this include higher vacancy rates on appellate courts, longer case-processing times and increased caseloads for judges.[8][41][43]

Political scientists argue that in highly polarized periods, nominees become less reflective of the moderate voter as "polarization impacts the appointment and ideological tenor of new federal judges."[43] It also influences the politics of senatorial advice and consent, giving partisan presidents the power to appoint judges far to the left or right of center on the federal bench, obstructing the legitimacy of the judicial branch.[41][43]

Ultimately, the increasing presence of ideology in a judicial system impacts the judiciary's credibility.[38] Polarization can generate strong partisan critiques of federal judges, which can damage the public perception of the justice system and the legitimacy of the courts as nonpartisan legal arbiters.[43][54]

Foreign policy

Political polarization can undercut unified agreement on foreign policy and harm a nation's international standing;[38][55] divisiveness on foreign affairs strengthens enemies, discourages allies and destabilize a nation's determination.[38]

Political scientists point to two primary implications of polarization with regards to the foreign policy of the United States". First, when the United States conducts relations abroad and appears divided, allies are less likely to trust its promises, enemies are more likely to predict its weaknesses, and uncertainty as to the country's position in world affairs rises.[55][56][57] Second, elite opinion has a significant impact on the public's perception and understanding of foreign policy,[56] a field where Americans have less prior knowledge to rely on.[55][56][58]

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