Written works of history unavoidably reflect the concerns of the time of their writing. The era of Trump has made its mark on historical writing, from Rick Perlstein issuing revisions of his picture of conservatism to Yale historian Timothy Snyder, never shy of courting controversy, becoming a full-on hashtag-resistance intellectual with his portentous warnings of tyranny in the offing.

Naturally, the dynamics of the moment have had their impact on history books dealing with the relatively recent past. It’s always a dicey game for historians to approach the present, but as the twentieth century recedes, the last decades of it become relatively safe ground. Or, it would be safe, if this wasn’t the logical place for historians to look for a way to explain the rise of Trump. Explaining Trump is hard enough. The effort of trying to explain Trump while holding on to an establishment liberal worldview is enough to warp any history.

Princeton historians Kevin Kruse and Julian Zelizer frame Fault Lines, their history of the United States since 1974, as the history of America’s growing divides. It is part of a growing literature, mostly coming from the social sciences but including journalism and now history, that tries to situate the problem of Trump as the result of social divisions. These divisions run along many axes — race, religion, gender, wealth, so on — but the ultimate division this literature talks about is that between conservatives and liberals; between the proverbial red and blue America. These works echo a similar literature produced during the George W. Bush years, but with much more panicky overtones.

Fault Lines describes the divides, and the many, many occurrences and developments that widened them in the last forty years. It does little to interrogate why these divides are where they are in the first place, and nowhere is this more pertinent than in the main divide the book examines, the red-blue divide. The authors goes so far as to make divisions of race, gender, religion, and class — all of which get a sub-chapter or two — germane to the text primarily as feeders of the red-blue conservative-liberal antagonism at the center of the book’s narrative. This is a curious choice in an era when the vast majority of Americans disapprove of both parties and a near-majority do not vote.

It’s not just the millions of Americans for whom red versus blue is a meaningless distinction that’s the problem with this focus. It’s that it leads to baffling historiographical decisions. The book describes division, but does not interrogate conflict, which means it has little to say about power. Very little changes in Fault Lines except that the divides get wider. The explanation for that is primarily technological (the rise of cable and the internet dividing the culture) and what amounts to personal (people got more extreme, mostly on the right). Kruse and Zelizer grant that the competing sides are in conflict over how society should be shaped. It’s clear they’re generally more sympathetic to the blue side than the red.

But getting at the actual power struggles in our society would take us above and beyond red versus blue, and especially into class politics that do not map onto our partisan divides in any neat way. Capitalists as a class are comfortable with either party — the poor and working classes find their status decline under both in the time period in question.

Bereft of a narrative through-line of meaningful struggle and taking the politics of the era at close to face value, there are parts of the book that read like nothing so much as medieval chronicles; that is, as chronological recitations of vaguely connected happenings, one after another. In this case, instead of the doings of kings and the results of harvests, most of these litanies are of things that irritated either red or blue Americans, most often red. Basic structures of our time (rising inequality) get conflated with important long-term political trends (the Protestant evangelical discovery of pro-life politics) that get conflated with memorable political moments (the Lewinsky scandal) which get conflated with ephemera (the misadventures of 2 Live Crew). MTV gets more attention than unions do (the PATCO strike is mentioned nowhere, tellingly) in Fault Lines and there’s a certain “greatest hits” flavor to these sections of the book as they take us from one well-known divisive episode to another.

What’s frustrating is that historians often make good use of ephemera, and they’re by no means bound to stick to the structural to say something relevant and profound about history. How did specifically partisan divides come to take on the valence they have? How did we wind up in a situation where 2 Live Crew were, for a moment, politically important? Is it just because of cable, or is there something more? These are worthwhile questions. Answers come from subjecting the dynamics involved to critical interrogation, and that occurs in Fault Lines fitfully, at best.

Taking our divisions both on face value and as a crisis in and of themselves leads to further questionable valuations. The authors bemoan the lack of a “shared American identity” in the opening to a chapter on black politics and immigration. “Rather than adopt the mainstream values of the white majority and adapt to its culture, racial and ethnic minorities increasingly sorted themselves into communities they made on their own terms and in their own images,” they write.

In what world do black, brown, and immigrant communities make themselves “on their own terms” and not in terms dictated by a racist system? In what world are those communities the ones seceding from society, and not the white upper and middle classes in their de facto segregated social enclaves? The answer to that is in a world where statements by assorted nationalists from communities of color weigh as much as the structures of racialized wealth, income, and inequality in access to social services.

This is a strange turn from two serious historians. Kevin Kruse wrote a sophisticated history of segregation and conservatism in Atlanta, and Julian Zelizer is a great proselytizer for a renewed focus on finely grained histories of American political institutions. This is where the Trump effect comes in. The election of Donald Trump was such a blow to so many deeply held liberal beliefs — from the theory that “the party decides” in presidential politics to basic assumptions about where history is going — that many are left scrambling for purchase on the situation. Kruse and Zelizer place a good deal of emphasis on Trump’s Russia connection towards the end of the book.

The idea that the country would do anything other than fully repudiate a potential Russian intelligence asset is enough to make the divides that (supposedly) produced this situation take on world-historical importance. Taking a step back and thinking about the larger dynamics at play — from inequality to America’s shaky global hegemony to climate change — must feel, in that situation, like an invitation to complicity. Unfortunately, it’s also the only way to make sense of our times.