Keith Ellison, the deputy director of the Democratic National Committee and congressman from Minnesota, recently ignited a Twitter firestorm when he tweeted out a picture of Antifa: The Anti-Fascist Handbook, a book, he declared, that would “strike fear in the heart of” Donald Trump. Upon reading Antifa, it’s easy to see why the tweet generated so much controversy.

Since its release last August, the handbook, by Dartmouth lecturer Mark Bray, has garnered attention as one of the few windows available into the mind of the newly prominent Antifa movement. Bray makes clear from the beginning that the book isn’t an attempt at a neutral rehashing of facts, but rather “is an unabashedly partisan call to arms” for the purpose of equipping activists “with the history and theory necessary to defeat the resurgent Far Right.” He articulates clearly the revolutionary ideology of the far left and defends using violence in its service, from street brawls to kidnappings to assassinations. For those who do not desire to see the world reborn in the flames of global anti-capitalist revolution, the popularity of The Anti-Fascist Handbook should prove alarming.

Antifa’s somewhat obvious immediate goal is the eradication of (what Bray considers to be) fascism. However, conveniently for Antifa, Bray argues that anti-fascist action is not merely limited to academic and historical definitions of fascism. Instead, “anti-fascism is an illiberal politics of social revolutionism applied to fighting the Far Right, not only literal fascists.” This meaning speaks to the broader end of the revolutionary left that Bray sees Antifa as a part of. This end, Bray explains, is the total destruction of the current capitalist order via a violent “international popular uprising.”

Bray’s many arguments against free speech—and in favor of violence—sound terrifyingly rational, at least in the context of his stated goals. The overthrow of capitalism most likely can’t be accomplished by working within the current state system, so there is no need to be concerned with the tenets of that system. Free speech, for example, plays a vital role in the preservation of our social harmony. Because of free speech, we talk instead of fighting when we have differences of opinion. When people think a law or regulation should be changed, they don’t start gunning down law enforcement officials or setting government agencies on fire. Rather, they lobby Congress or campaign for representatives who will enact the changes they desire. This system is far from perfect and it allows many injustices to be perpetrated, but it’s much more attractive than the alternative in which violence is allowed to settle disputes and enact political change.

However, for the revolutionary left, the total elimination of injustices—not just their minimization—is the goal. Rather than viewing free speech as a way to keep things from becoming worse, Bray flat out rejects the First Amendment as a tool that can be used by oppressors. In his words, “at the heart of the anti-fascist outlook is a rejection of the classical liberal phrase…‘I disapprove of what you say, but I will defend to the death your right to say it.’” Instead, Bray opens the book with a quote from a leftist revolutionary killed in the Spanish Civil War: “[F]ascism is not to be debated, it is to be destroyed!”

Perhaps it could be justified, under the most extreme of circumstances, to curtail some speech, for instance, if the literal incarnation of Hitler were to start giving rousing speeches at bars across the country. However, Bray makes clear that, from the anti-fascist point of view, such a farfetched scenario would mean it’s already too late; instead, potential Nazi movements must be stifled in their infancy. This allowance leads to an ever-increasing number of people who need to be destroyed. For Bray, politicians like President Trump, media figures like Ann Coulter and Bill O’Reilly, and intellectuals like Charles Murray all deserve to be nipped in the bud speech-wise due to their opinions.

By the time he’s finished, Bray has thrown everything and the kitchen sink into the category of fascist ideologies that must be targeted, ranging from whiteness to “ableism, heteronormativity, patriarchy, nationalism, transphobia, class rule, and many others.” Though cloaked in calls to stop oppression, Bray’s book at its core makes the case for the exercise of raw, unbridled power. Under this revolutionary ideology, no dissent can be tolerated. There can be no live and let live—it is all or nothing.

The 20th-century political philosopher Eric Voegelin argued that at the core of all revolutionary ideologies was the libido dominandi, a lust to control and dominate. Bray may claim to advocate for anti-authoritarian socialism, but his naked embrace of violence against all who oppose him and his ideological fellows makes clear that, were Antifa to achieve significant power, the result would be no different from any of the other deadly socialist revolutions we’ve seen.

The Anti-Fascist Handbook is necessary reading for all those who wish to defend a free society, in order to understand the illiberalism they’re up against.

Zachary Yost is a Free Society Fellow with Young Voices and lives in the Pittsburgh area. Follow him on Twitter @ZacharyYost.