Why do people who identify themselves as liberal or egalitarian sometimes embrace intolerance or even preach violence? Illiberalism has come to be expected of the right in this country; its occurrence on the left is more paradoxical but no less real.

In this book, Richard J. Ellis examines the illiberal tendencies that have characterized egalitarian movements throughout American history, from the radical abolitionists of the 1850s to the New Left activists of the 1960s. He also takes on contemporary radical feminists like Catharine MacKinnon and radical environmental groups like Earth First to show that, even today, many of the American left's sacred cows have cloven hooves.

He explains how orthodoxy arises within a group from the need to maintain distance from a society it views as hopelessly corrupt, and how individuals committed to egalitarian causes are particularly susceptible to illiberalism - even poets like Walt Whitman, who celebrated the common people but often expressed contempt for their mundane lives.

Political correctness, idealizing the oppressed, and an affinity for authoritarian and charismatic leaders are all parts of what Ellis calls "the dark side of the left."