Kevin M. Kruse and Julian E. Zelizer, the authors of Fault Lines: A History of the United States Since 1974, are award-winning scholars of twentieth-century American political history. Fault Lines grew out of the hugely popular course that they cocreated at Princeton University, The United States Since 1974.

The 2020 election has been a sobering experience for many Americans. Even after living through all the drama of the Trump presidency as well as the pandemic, the first few nights of election returns provided a reminder of just how deeply divided the nation remains. 

Despite predictions of a potential landslide for former vice president Joe Biden, the contest came down to a handful of battleground states, with small slivers of voters being critical. The swing states of 2016 — Wisconsin, Michigan, and Pennsylvania — were all front and center once again, as well as a few new ones, such as Arizona and Georgia. The national maps showed a country divided into red and blue camps, and the maps of individual states showed the same polarization at the county level.

The persistent divisions in the United States since the 1960s — which we refer to as “fault lines” — serve as the key integrative framework in our class and the work we do, but it’s not work we do alone. Teaching college and high school students about the origins and evolution of recent partisan polarization is more important than ever before. The younger generation of Americans want to know more about how this situation came to be, and we all have a duty to help them understand how we ended up here and how we might get out of it. 

A starting point is understanding the history of the individuals, movements, and trends that shaped the modern landscape. Just as we have histories of liberalism and conservatism in America, or histories of the family and gender, we need to present the historical development of political, social, and economic divisions in order to teach the events of the recent past through an analytical historical lens. In our class, we bring these divisions into relief by focusing on the “fault line” issues that have have deepened our partisanship — such as income inequality, racial divisions, and the revolution in gender roles and sexual norms — and we explore the impact that innovations in communications and technology have had in making them become so pronounced since the 1970s. 

In our lectures, we discuss a number of key personalities — such as Lee Atwater, Newt Gingrich, and Mitch McConnell — who helped dismantle the postwar consensus and launch the hyperpartisan politics of our own time. We show how Donald Trump took advantage of these preexisting divisions and aggravated them, while reminding that the phenomena that helped create his presidency will surely outlast it.

We also examine the institutions that have fueled the divisions and will continue to do so in a post-Trump world. We have, for instance, paid close attention to the evolution of the news media, looking first at the creation of a 24-hour news cycle with the advent of cable television, then the emergence of openly partisan news norms with the abandonment of the Fairness Doctrine in 1987 and the establishment of Fox News in 1996, and finally the breakdown of editorial filters with the growth of the Internet. Likewise, we look at other institutions in America that have an interest in perpetuating and deepening the red/blue divide, such as the Congress, whose internal organization has privileged partisan power and social movements that have pulled voters in very different directions on core issues. 

Building our course around these “fault lines”has also helped us think about how to teach about American politics and society in an era when the classroom itself is increasingly divided. Students enter into our lecture halls and seminar rooms often with very different interpretations of key moments in the past. Both of us have worked hard to foster constructive debates. Rather than attempting to create classrooms that move collective opinion in either direction, we have always aimed to create a structured framework for smart deliberation. Students with different perspectives are pushed to refine their arguments and to better understand those who disagree. We insist on keeping the discussion grounded in the historical facts, pushing back when students veer into pure opinion. The beauty of historical studies is that it can push students to analyze concrete facts, dates, and figures — the kind of material too often missing in the public sphere.

In Professor Zelizer’s current iteration of the class upon which Fault Lines is based, he includes a number of paper assignments that have students wrestle with original historical material to understand politics. During some semesters, we have asked students to use History Proquest to do research and write papers about the context behind historic speeches — such as Jimmy Carter’s “malaise” speech in 1979 or George W. Bush’s 9/11-era speeches — or to better understand how speeches were received or became moments of controversy. More recently, Zelizer asked students to use the same source archive to write papers about specific events that don’t always receive attention in textbooks, such as the Major League Baseball strike in 1994–95 — which is a great case study on the changing nature of labor-management relations and economic inequality — or the violent and tragic Crown Heights race riots in 1991, involving the Black and Orthodox Jewish communities in New York City. Using the tools of analysis from the course, students consider the long-term implications of these incidents and place them in some broader historical context.

Teaching about moments such as the 2020 election is challenging, but contemporary history in fact offers a perfect way for students to step out of the frenzy in which they live and start to dispassionately understand how and why we reached this point. By focusing on current events, we can start good conversations about what’s gone wrong in the past and how we as a nation might put it right.