On September 18, 2025, President Donald Trump set off a political firestorm by declaring on his Truth Social platform that he intends to designate Antifa—a decentralized, leftist movement known for its opposition to far-right and fascist groups—as a "major terrorist organisation." The announcement, coming just days after the fatal shooting of conservative activist Charlie Kirk, has reignited fierce debate over the nature of Antifa, the limits of presidential power, and the broader landscape of political violence in the United States.
Trump’s message was blunt and characteristic: he labeled Antifa a "sick, dangerous, radical left disaster" and vowed that the group would be "thoroughly investigated." According to BBC News, the president’s move is part of a larger campaign against what he calls the "radical left," a campaign that has intensified in the wake of Kirk’s killing—a tragedy that Trump and his allies have linked, at least rhetorically, to Antifa and related left-wing activism.
But what exactly is Antifa? The very name is short for "anti-fascist," and its roots stretch back to 1930s Germany, where anti-fascist groups fought against the rise of Nazism. In the United States, Antifa has existed in various forms for decades, but it truly rose to national prominence following Trump’s first election victory in 2016 and the infamous Charlottesville rally in 2017. Since then, Antifa-affiliated activists have been a fixture at protests, often pitted against right-wing groups in heated—and sometimes violent—confrontations.
Yet Antifa is not an organization in the traditional sense. As The Washington Post and BBC News both point out, it is a loose, leaderless affiliation of activists, many of whom identify as anarchists, communists, or hardline socialists. There is no central command, no membership list, and no clear structure. Antifa “cells” tend to form organically, both online and offline, united by a shared opposition to fascism, racism, and, more broadly, right-wing extremism. Their views often lean anti-government, anti-capitalist, pro-LGBTQ, and pro-immigration, but the movement itself is far from monolithic.
This decentralized nature is precisely what makes Trump’s proposed designation so contentious—and, according to many experts, potentially unworkable. In testimony before Congress back in 2020, then-FBI Director Christopher Wray described Antifa as "more of an ideology than an organization," a view echoed by legal scholars in recent days. Luke Baumgartner, a research fellow at George Washington University's Program on Extremism, told BBC News, "There is no legal mechanism I'm aware of that would formally establish any group as a domestic terror organisation." He added, "As far as I know it's just a proclamation on Truth Social which means nothing, and unless Congress wants to take concrete steps I don't see that happening."
Indeed, the U.S. government’s ability to designate terrorist organizations is generally limited to foreign groups. The State Department maintains a list of Foreign Terror Organizations (FTOs), which includes groups like ISIS and, increasingly, certain drug cartels. But there is no equivalent process for domestic groups, and any attempt to create one would likely run headlong into First Amendment protections for free speech and association. Professor David Schanzer, director of the Triangle Center on Terrorism and Homeland Security at Duke University, explained to the BBC: "The First Amendment protects the right of association, which encompasses the right of individuals to form groups and prohibits the government from interfering with the operations of those groups, unless of course, they have violated the law." He added pointedly, "The president's designation of such a group as a 'major terrorist organisation' does not change those fundamental constitutional rights."
Brad Evans, a professor of political violence at Bath University, warned that Antifa’s lack of formal structure "offers a remarkable opportunity to extend the [government's] remit and apply it to anybody who may be assumed to belong to an organisation that is ill-defined." This, he cautioned, means that "anybody suspected of belonging to Antifa, would need to disprove their association. The dangers of overreach are all too apparent."
Critics of Antifa, particularly on the right, argue that what sets the movement apart from other left-wing groups is the willingness of some of its activists to use violence. There have been well-documented incidents: in 2017, around 100 masked activists carrying Antifa-linked signs and flags attacked a group of right-wing protesters in Berkeley, California, resulting in multiple arrests. During the unrest following the killing of George Floyd in 2020, Michael Reinoehl, a self-proclaimed Antifa activist, shot and killed a supporter of the far-right group Patriot Prayer in Portland; Reinoehl was later killed by police. Antifa activists are also known for "doxxing"—publicly releasing the identities and personal details of individuals they deem to be far-right activists, with the aim of social ostracization or job loss.
In the immediate aftermath of Charlie Kirk’s killing, BBC Verify reported that some self-identified Antifa members defended the shooting on social media platforms like Reddit and X. However, authorities have said that Tyler Robinson, the man accused of Kirk’s murder, had a "leftist ideology" but have provided few specifics, and he has not been directly linked to Antifa.
Trump’s latest move is not without precedent. He first floated the idea of labeling Antifa a terrorist organization in 2020 but did not follow through at that time. This renewed push comes as part of a broader crackdown on what Trump and his supporters describe as "radical left political violence." In his own words: "Radical left political violence has hurt too many innocent people and taken too many lives." Still, the legal and practical barriers to such a designation remain formidable.
The controversy also comes amid shifting narratives about political violence in America. This week, the U.S. Department of Justice quietly removed a 2024 study from its website that had concluded far-right extremism outpaced "all other types of violent extremism" in the country. When asked by the BBC why the study was removed, the department declined to comment. Independent studies reviewed by BBC Verify have consistently found that right-wing extremists have committed more acts of political violence in the U.S. than left-wing extremists, though researchers caution that definitions of "right" and "left" can be inconsistent.
Professor Robert Pape of the University of Chicago noted that recent years have seen "historic highs in political assassinations and assassination attempts," with both Republican and Democratic politicians targeted. He observed, "What we see in our data on what happens when a political leader blames one side for the violence is it produces more support for political violence, not less."
As the debate continues, the question remains: can a loosely defined, leaderless movement like Antifa be meaningfully targeted by federal law? And, perhaps more importantly, will such efforts bring the country closer to peace—or only deepen its divisions? For now, Trump’s proclamation is as much a signal to his political base as it is a policy proposal, but the legal and constitutional challenges ahead are likely to keep this issue in the headlines for months to come.
