The article "Putting Polarization in Perspective" by Marc J. Hetherington provides a comprehensive analysis of the state of polarization within American politics, focusing on both elite and mass levels:

• Introduction to Polarization:
  • American political elites have significantly polarized over the past three decades, with a clearer divide in partisan alignment. However, there is debate on whether the American electorate mirrors this polarization. The article evaluates evidence, causes, and consequences of polarization, finding a stark contrast between elite polarization and the generally centrist attitudes of the mass populace.
• Elite Polarization:
  • Historical context reveals that the current state of elite polarization, characterized by partisanship and ideological divides within Congress, is not entirely new. Such divisions have been present at various points in American history, though the post-World War II era was notably more consensual.
  • The causes of elite polarization are multifaceted, involving both institutional changes within Congress (such as changes in party leadership dynamics and the rules governing legislative processes) and broader societal shifts (like demographic changes and variations in regional political alignment).
• Mass Polarization:
  • Contrary to elite polarization, the evidence for mass polarization is mixed. While political choices may seem polarized due to the options presented by the political arena, many Americans continue to hold moderate views. Disagreements on the extent of mass polarization often stem from differing definitions of polarization itself.
• Impact of Polarization:
  • Elite polarization without corresponding mass polarization could potentially alienate a moderate public, affecting political participation and policy outcomes. This discrepancy might lead to policies that do not reflect the preferences of the majority of Americans. The article suggests that the supermajoritarian nature of the US Senate acts as a check against ideologically extreme policy outcomes.
• Causes of Polarization:
  • The roots of contemporary elite polarization can be traced back to shifts in the political and ideological compositions of Congress, driven by regional realignments, demographic changes, and alterations in the electoral system. These changes have facilitated a more pronounced ideological divide between and within the major political parties.
• Mass Polarization vs. Party Sorting: The article suggests little evidence of popular polarization, defined as the general public moving towards extreme ends of the political spectrum. Instead, it finds strong evidence of party sorting, where individuals align more consistently with a political party's ideology, leading to a more ideologically homogenous party base but not necessarily to individual extremity in views.
• Definition and Measurement of Polarization: Polarization is operationally defined through the dispersion of preferences between groups, aiming for bimodality or clustering of preferences near the poles. This definition faces limitations, as survey responses tend to depress dispersion, making it difficult for respondents, especially the less informed, to cluster towards ideological poles.
• Evidence Against Popular Polarization: Despite the prevalence of divisive issues, most Americans' issue preferences remain moderate. Ideological self-placement data show that about 50% of Americans identify as moderate or are unable to place themselves on the ideological scale, indicating a lack of popular polarization.
• Salience and Issue Weight in Polarization: The article argues that salience, or the importance attached to issues, can make issues seem more polarizing even if distances between groups remain small. An issue's weight can increase its effect on perceived polarization, suggesting that while there may not be a significant movement towards ideological poles, issues of high salience can still cause a polarized environment.
• Contributors to Party Sorting: Several factors contribute to party sorting, including:
  • Elite-level polarization, which provides clearer cues for voters to align their party affiliations with their ideological beliefs.
  • Changes in the mass media landscape, with more adversarial and interpretive reporting potentially encouraging polarization.
  • Campaign strategies focusing on mobilizing base voters and attracting "cross-pressured" voters through highlighting divisive social issues.
• Consequences of Party Sorting: While sorting has not demobilized the electorate, it has led to an environment where party affiliation serves as a stronger filter for information, influencing perceptions and evaluations of political figures and policies more than before. This increased effect of partisanship is evident in phenomena like the highly partisan views on the Iraq War and factual beliefs about political issues.
• The Role of George W. Bush's Presidency: The presidency of George W. Bush is highlighted as a period of significant polarization, with strong partisan divisions in approval ratings and views on the Iraq War. The article poses the question of whether this environment is unique to Bush's presidency or indicative of a broader trend towards polarization and sorting in American politics.

This detailed analysis presents a nuanced view of polarization in the United States, emphasizing the distinction between elite polarization and mass sorting, and the complex interplay of factors contributing to the current political landscape.