Over the weekend we learned that President Trump — who has taken credit for an economic turnaround that began under Barack Obama and a hot streak by the Boston Red Sox — insists that he predicted the meteoric rise of Representative Alexandria Ocasio-Cortez long before anyone else did. He says that he called her “Evita,” comparing her to Eva Perón, Argentina’s populist first lady, ahead of Ocasio-Cortez’s surprise victory in the Democratic primary of 2018.

On Sunday, The Guardian disrupted the publisher’s carefully scheduled rollout of Tim Alberta’s “American Carnage: On the Front Lines of the Republican Civil War and the Rise of President Trump” by leading with this morsel from Alberta’s reporting. Before the end of the day, the online furor had run its course — from amplification and distrust to playful irony and political mudslinging. Ocasio-Cortez tweeted out Perón quotes about helping the poor; conservatives gleefully used her tweets to bring up how Argentina under the Peróns became a haven for Nazi war criminals.

It’s a sign of the times that Alberta’s doorstop volume was at first reduced to a sound bite from the president, who has an uncanny gift for making everything about him. But “American Carnage” isn’t just another drop in the deluge of Trump books; in fact, it isn’t really a Trump book at all. Instead it’s a fascinating look at a Republican Party that initially scoffed at the incursion of a philandering reality-TV star with zero political experience and now readily accommodates him.

Alberta, a political correspondent for the conservative magazine National Review before moving to Politico, brings more than a decade of reporting and a real understanding of the conservative movement to “American Carnage.” He reminds readers of the 2000 presidential election, when George W. Bush campaigned with the promise of “compassionate conservatism,” reflecting an attempt by the Republican Party to present itself as “warm, aspirational, inclusive,” pursuing minority outreach and immigration reform. Republican pollsters had taken a look at the changing demographics of the country, and the numbers spelled doom. The Republican Party simply couldn’t survive by catering primarily to white people.