PARTY POLARIZATION IN AMERICAN POLITICS: Characteristics, Causes, and Consequences

Abstract

Recent commentary points to clear increases in ideological polarization between the major American political parties. We review the theoretical and empirical literature on party polarization and partisan change. We begin by comparing the current period both to earlier political eras and to theories of partisan change. We argue that in the current period the parties have grown increasingly divided on all the major policy dimensions in American politics-a process that we term conflict extension. We discuss various perspectives on increases in polarization between the parties in government, the parties in the electorate, and the parties' activists, and we consider the causal links between polarization at each of these levels. We consider whether American society itself, and not just the parties and their identifiers, has become increasingly polarized. Finally, we discuss the consequences of growing party polarization for American political life.

Partisans without Constraint: Political Polarization and Trends in American Public Opinion

“…In other words, since the parties are now more clearly divided-and on a broader set of issues-it is easier for people to split accordingly, without changing their own views (this is why we use the term illusory). There has been some discussion regarding the directionality of the change, with most scholars suggesting that public opinion polarization is a consequence of elite polarization (Layman et al 2006). Our results confirm this interpretation, since, despite partisan alignment, we found no real instances of issue alignment.…”

“…As documented by the extensive analysis of congressional roll-call voting Rosenthal 1984, 2007;Rohde 1991;Aldrich 1996), interest groups' ratings (Poole and Rosenthal 2007, chap. 8), and other sources (Layman, Carsey, and Horowitz 2006), members of Congress have aligned at opposite ends of the liberal-conservative spectrum, and the number of moderate representatives has steadily decreased.…”

“…The electoral realignment of the southern states (Carmines and Stimson 1989;Rohde 1991;Layman et al 2006;Ansolabehere and Snyder 2008) and the mobilization, in the middle of the 1960s, of grassroots conservative groups during the Goldwater campaign (Perlstein 2001;Brady and Han 2006) marked the beginning of a consistent movement of the Republican Party toward more conservative positions. Exiting moderate Republican members of Congress were replaced by a new cohort of socially conservative Republicans.…”

“…Indeed, activists have become more important in the selection of party nominees in recent decades, and they tend to have more radical views than the average citizen. In addition, the growth, starting in the 1970s, of single-issue-based interest groups has had a radicalizing effect on parties' primaries and legislative behavior in Congress (Saunders and Abramowitz 2004;Brady and Han 2006;Layman et al 2006). Polarization shows similar trends among activists as among congressional representatives, although a clear causal relation has yet to be established.…”

Partisan polarization and US foreign policy: Is the centre dead or holding?

“…As a consequence, votes in Congress frequently saw two bipartisan coalitions voting against each other. It is generally accepted, however, that since the early 1970s partisan polarization has been steadily increasing at the level of party elites and within Congress Hetherington, 2001Hetherington, , 2009Jacobson, 2010;Layman et al, 2006;Levendusky, 2009;McCarty et al, 2006;Poole and Rosenthal, 1984;Sinclair, 2006;Stonecash et al, 2002;Theriault, 2008;Voteview.com, 2012Voteview.com, , 2014. 1 Analysis of DW NOMINATE scores up to the end of the first session of the 113th Congress, for example, demonstrates that the ideological gap between the parties is now greater than at any point since Reconstruction (Voteview.com, 2014).…”