• Sam Rosenfeld

    Visiting Assistant Professor of Government

    Hamilton College

  • Biography

    Welcome! Currently a Visiting Assistant Professor of Government at Hamilton College, I will be an Assistant Professor of Political Science at Colgate University starting in July of 2017. I have a PhD in History from Harvard University and study political parties and American political development. My research interests include the history of political parties, the intersection of social movements and formal politics, and the politics of social and economic policymaking. My book project, The Polarizers: Postwar Architects of Our Partisan Era (forthcoming January 2018, University of Chicago Press), offers an intellectual and institutional history of party polarization in the postwar United States.


    I previously worked as a writer and editor at The American Prospect magazine in Washington, DC, where I continue to contribute articles. I hold a BA in History from Columbia University and an MA in History from Harvard.

  • The Polarizers: Postwar Architects of Our Partisan Era

    Chicago Daily Tribune, February 18, 1957


    My book project, forthcoming with the University of Chicago Press, traces the construction of an ideologically defined party system in the United States during the second half of the 20th century. Its core argument is that the contemporary era of party polarization did not emerge merely as the byproduct of long-term structural developments, but was a political project carried out by conscious historical actors across the postwar decades. The work of activists, reformers, and political elites within and around the Democratic and Republican parties helped to produce, by the end of the century, an unpredicted and still-continuing period of strong, polarized partisanship in American politics. In tracking that work, the book also accounts for changing ideas about the party system over time—starting with a postwar scholarly doctrine that cast bipartisanship as a problem for which polarization would provide the solution. Spanning four decades of dramatic political conflict, issue-driven activism, and institutional reform, the narrative provides an origins story for the dynamics and dysfunctions that define the modern political era.


    Partisan polarization structures contemporary American politics and dominates popular discussion of it. But the history of this development has been told only in fragments, and the transformation of the American party system remains marginal to the main scholarly themes of later-twentieth-century historical scholarship. This book brings that unheralded transformation and its architects to the center of the story of modern American politics. The project enriches the abundant popular and scholarly discussion of contemporary party polarization, identifying its origins in developments dating to the early postwar years and historicizing Americans’ long-running debates over partisanship. Placing purposive actors at the center of the story addresses a key shortcoming in dominant political science accounts of polarization, which identify elite-level polarization in the later twentieth century as the spur to ideological sorting in the mass electorate but render the process of that initial elite polarization a historical black box. By specifying the actors who made polarization happen and connecting their actions to a shared set of normative views about party politics, this book opens that black box. The book’s institutional focus also helps to recast and revise key historiographic narratives of post-1960s U.S. politics, particularly the rise of the right and the decline of the New Deal order. It does this by framing the period’s conservative mobilizations as a partisan project and by highlighting processes of ideological consolidation and organizational change within the Democratic Party and among allied groups that paralleled developments on the right.

    Chapter outline

    A detailed chapter summary can be found here.



    Chapter One: The Idea of Responsible Partisanship, 1945-1952

    Chapter Two: Democrats and the Politics of Principle, 1952-1960

    Chapter Three: A Choice, Not an Echo, 1948-1964

    Chapter Four: Power in Movement, 1961-1968

    Chapter Five: The Age of Party Reform, 1968-1975

    Chapter Six: The Making of a Vanguard Party, 1968-1980

    Chapter Seven: Liberal Alliance-Building for Lean Times, 1972-1980

    Chapter Eight: Dawn of a New Party Period, 1980-2000

    Conclusion: Polarization Without Responsibility, 2000-2016

  • Publications and Media

    Peer reviewed publications

    Works in progress

    The Polarizers: Postwar Architects of Our Partisan Era (University of Chicago Press, 2018).


    "The Hollow Parties," (book chapter with Daniel Schlozman).


    "The Declinist Era in Party Scholarship: An Intellectual History" (working paper).


    "Constructing a More Responsible Two-Party System: Liberal Origins of Modern Party Polarization" (working paper).


    Working paper on the 1968 Democratic challenge delegation in Georgia (with Nancy Schwartz).

    Selected other publications

    "There's No Going Back," review of The Great Exception by Jefferson Cowie, Democracy: A Journal of Ideas (Spring 2016).


    "Should Liberals Back Public Employee Unions?," review of Government Against Itself by Daniel DiSalvo and Bring Back the Bureaucrats by John J. DiIulio, Jr. The American Prospect (Summer 2015). With Jake Rosenfeld.


    Smooth Operator,” review of The Whole Damn Deal by Kathryn McGarr. The American Prospect (September 2011).


    A Long-Distance Runner,” review of Citizen Rauh by Michael E. Parrish. The American Prospect (December 2010).


    Frustrated by His Own Party,” review of Roosevelt's Purge by Susan Dunn. The American Prospect (November 2010).


    The Way of the Hammer,” feature article on the uses of congressional partisanship. The American Prospect (November 2006).


    The Truth About the Senate,” review of The Most Exclusive Club by Lewis Gould. The American Prospect (December 2005).


    Disorder in the Court,” feature article on liberal and conservative critiques of judicial review. The American Prospect (July 2005).


    Recent media appearances and mentions

    Interviews on CTV News, July 21, 2016 and November 9, 2016.


    Maurice Isserman, "How to Make the Democratic Party Platform Actually Matter," In These Times, July 15, 2016.


    E.J. Dionne, "Fighting nostalgia and amnesia in America's search for lost greatness," Washington Post, July 6, 2016.


    Alan Greenblatt, "The Freedom Caucus' Unprecedented Insurgency," Politico, October 18, 2015.


    Matthew Yglesias, "American democracy is doomed," Vox, October 8, 2015.


  • Teaching

    Courses taught

    Topics in Public Policy: College Financing, Hamilton College, Spring 2017 - Syllabus

    Senior Project Seminar: The American Welfare State, Hamilton College, Spring 2015 and Spring 2017 - Syllabus

    American Political Development, Wesleyan University, Spring 2015, Hamilton College, Fall 2016 - Syllabus

    Political Parties and Elections, Hamilton College, Fall 2014, Fall 2016 - Syllabus

    American Political Parties, Wesleyan University, Fall 2015

    American Government and Politics, Wesleyan University, Fall 2015 and Spring 2016

    The American Political Process, Hamilton College, Fall and Spring 2014 - Syllabus

  • Contact

    Sam Rosenfeld

    Visiting Assistant Professor, Government Department

    Hamilton College

    198 College Hill Rd

    Clinton, NY 13323