Political polarization is easily one of the most active areas of research on American politics. However, in recent years, the central question of this research has shifted to focus on the partisan affect of ordinary citizens. As befits a question arising from social psychology, this work has focused on survey-based measurements and experimental manipulation to uncover the factors underlying voters’ increasing attachments to the in-party and animosities toward the out-party. While this vast research on affective polarization has uncovered useful insights, it has generally ignored an older research tradition, which focuses on polarization as an elite-driven process with deep historical and institutional roots.

In their new book, Partisan Nation: The Dangerous New Logic of American Politics in a Nationalized Era, Paul Pierson and Eric Schickler seek to reassert the importance of institutional politics and historical development in our understanding of the origins and consequences of party polarization in the US. The book’s motivating question is whether polarization is the natural state of American politics or whether the system is prone to reverting back to moderation and cross-cutting cleavages. Pierson and Schickler argue that, throughout most of its history, the “Madisonian Constitution” served to dissipate polarized conflict and to maintain political moderation and stability. To be sure, there were intense episodes of partisan conflicts, such as those associated with the Federalist-Jeffersonian party system, with the Civil War, and with industrialization in the late 19th century. But in each of these cases, a set of “mediating” institutions created and sustained by the highly federalized order provided openings for cross-cutting coalitions that subverted the dominant dimension of polarized conflict. These mediating institutions include autonomous state parties and local media, which forced elected officials to be very responsive to localized economic and social interests.

The authors productively apply this logic to interpret several key instances of depolarization in US history, such as the formation of a cross-cutting coalition of artisans and mechanics with agrarians within the Jeffersonian Republican Party, the media-organized fusion ticket of Democrats and Liberal Republicans in 1872 that sought to moderate Reconstruction, and the revolt against Speaker Joseph Cannon and the emergence of a Republican progressive movement in the early 20th century. It is obviously worth noting that the examples of the 1872 fusion ticket and the later incorporation of Southern segregationists into the New Deal coalition clearly demonstrate that reducing political polarization is not always a good thing.

But over the past half-century, these mediating guardrails have broken down at the hands of an increasingly nationalized political system. As national issues began to predominate, voters shifted allegiances from regionally idiosyncratic politicians toward those representing national party brands. Once powerful and independent state parties not only lost their crucial role in the selection of presidential candidates but also in the nomination of local ones. A nationalized and internationalized economy shrunk the sphere of truly localized interest groups and forced many groups into increasing partisan coalitions. Finally, the devaluing of local political coverage led citizens to seek out the newer nationalized media technologies of cable and social media, leading to the demise of political coverage with a local angle. As a consequence, few politicians today have the incentive to deviate from the national political cleavages to support localized interests, or so Pierson and Schickler argue.

Despite its thought-provoking arguments and its appeal to substantial historical and contemporary evidence, several aspects of the book could have been analytically sharper. In particular, the authors’ account of nationalization is much slimmer than their account of polarization despite its importance to their argument. They attribute nationalization primarily to the consequence of the extensive national policymaking of the “Long 1970s,” which made control of the federal government more consequential for parties, activists, and citizens. But there is no deeper account of centralizing political and economic forces that helps to explain why the nationalization of the 1960s and early 1970s arose and was sustained. A deeper account could have shed light on the question of whether nationalization merely enabled the sustained polarization of today or whether it was a driving cause.

Second, their superordination of racial conflict above other contemporary political issues does not deeply engage the literature on public opinion and roll-call voting on the structure of mass and elite opinions. While racial attitudes clearly differentiate partisans, much of this work covering the 1990s through the 2010s found that political attitudes and behavior were more clearly structured around divergent views on redistribution, economic policy, and the role of the federal government. While there is some evidence that economic issues may have been displaced as the leading cause of polarization over the last decade, this fact would, of course, have consequential for their argument about the durability of polarization.

Finally, Pierson and Schickler treat Donald Trump’s GOP as the linear extrapolation of the party that emerged in the 1970s and 1980s. While there are certainly many continuities, the current GOP is much different from that which Donald Trump inherited from Mitt Romney and Paul Ryan (or from Ronald Reagan, for that matter). In certain aspects, the contemporary GOP is indeed more polarizing. It more overtly tropes in white-identity politics, demonizes political opponents, and plays constitutional hardball. But it is important to note the many ways in which Donald Trump has taken positions on many issues that would certainly be coded moderate when compared to the Romney-Ryan baseline, especially on entitlements and skepticism toward free trade and globalization. As a candidate in 2024, President Trump even jilted many of his most fervent supporters by opposing a national abortion ban. It would have been interesting to see the authors grapple more with the implications of the simultaneous polarization and depolarization of the Trump era.

In the book’s final chapters, Pierson and Schickler draw out the implications of polarization—focusing especially on the transformation of the GOP—for the performance and sustainability of America’s democracy. They are not optimists. They straightforwardly conclude that James Madison’s guiderails have almost completely washed away, leaving few impediments to greater polarization and to further executive and judicial encroachment as Congress is beset by gridlock and distorted incentives for oversight. Moreover, they note that the structural advantages of the GOP, such as the Electoral College, the basis of Senate representation, and the geography of single-member House districts, have somewhat insulated the party from electoral accountability. They argue that the most popular items on the reform agenda are neither likely to be effective nor politically viable. The outcomes of the 2024 election and restoration of the Trump presidency suggest that such pessimism is not unwarranted.