Ever since the 2016 election of Donald Trump as president, it's become common to hear that America hasn't been this politically divided in decades. One could make a convincing case that it's been five decades, to be exact — the 1968 presidential election was one of the most dramatic in American history, and it happened as the country was being torn apart by rage and violence.

As Michael Schumacher writes in his fascinating new book, "The Contest," "The overheated rhetoric and violence of 1968 backed one into dark, unexplored regions of the mind." The election and its aftermath would force the nation to confront these regions, and what we learned about ourselves was beyond painful.

Schumacher's book is an exhaustive look not just at the 1968 election, but at the social changes that brought the country to that particular boiling point. It's divided into four large sections, a structure that's well suited for a topic with so many layers and personalities.

In the first section, Schumacher offers profiles of the five major players in the election: Richard Nixon, George Wallace, Robert Kennedy and Minnesotans Hubert Humphrey and Eugene McCarthy. He seems particularly fascinated with the latter two, and he does a good job of contrasting Humphrey's backslapping bonhomie with McCarthy's academic coolness.

The book's second section focuses on the major primaries, including the contests in New Hampshire, Wisconsin and California, the last of which Kennedy won just before he was shot to death in Los Angeles. Schumacher's handling of Kennedy's assassination is sensitive and dramatic, and indeed, so is his writing throughout the book — he keeps the reader turning the pages, even though we know what the outcome is.

The final two sections of the book deal with the conventions and the general election, which of course culminated in a victory for Richard Nixon, who, Schumacher notes, then "embarked on an inglorious destiny." (Schumacher, who has written biographies of left-wing artists Allen Ginsberg and Phil Ochs, does not hide his distaste for the famously corrupt Republican from California.)

It's difficult to imagine a more compelling and comprehensive look at the 1968 election than Schumacher presents in "The Contest." And it's impossible to read without noting the parallels between then and now, as a nation struggles to keep believing in itself. As Schumacher writes, "It is a story of faith — and the loss of it. It is a story of change."

Michael Schaub is a regular contributor to NPR and the Los Angeles Times and a member of the board of the National Book Critics Circle. He lives in Austin, Texas.

The Contest: The 1968 Election and the War for America's Soul
By: Michael Schumacher.
Publisher: University of Minnesota Press, 540 pages, $34.95.