President Trump’s latest move to label antifa as a “major terrorist organization” has reignited a fierce debate in Washington and across the country. Announced on September 17, 2025, during a state visit to England, Trump’s declaration comes in the wake of the assassination of conservative activist Charlie Kirk—a crime for which the accused, Tyler Robinson, has not been publicly linked to antifa. Still, the president and several Republican leaders are calling for increased scrutiny of the left-wing movement, including investigations into its purported funders.
But what does it actually mean to designate antifa as a terrorist group? And, perhaps more importantly, is it even possible under U.S. law? According to experts cited by both NPR and CBS News, the answer is a resounding “no.” There is no legal framework for designating domestic groups as terrorist organizations in the United States—a fact that has not stopped the political rhetoric, but certainly complicates any real-world consequences.
Antifa, short for “anti-fascist,” is not an organization in the traditional sense. As the Congressional Research Service and multiple academic experts have noted, it is a decentralized collection of radical, independent groups and individuals. Its roots trace back to anti-racist activism opposing the Ku Klux Klan and neo-Nazis, but it gained mainstream attention after violent clashes in Charlottesville, Virginia, in 2017. Michael Kenney, a professor at the University of Pittsburgh who has studied antifa, told CBS News, “There is no single organization called antifa. That’s just not the way these activists have ever organized themselves. There’s tremendous variation inside that movement, even on issues like political violence.”
Despite the lack of formal structure, antifa has become a frequent target for Trump and his allies, who blame it for episodes of political violence. In his announcement, Trump argued that “radical left wing political violence” is “directly responsible for the terrorism that we’re seeing in our country today, and it must stop right now.” This echoes his rhetoric from his first term, when he called for antifa to be designated as a terrorist organization following unrest after the killing of George Floyd in 2020.
Yet, as Faiza Patel of the Brennan Center for Justice told NPR, “There is no framework to designate an organization as a domestic terrorist organization.” The State Department does have a process for labeling foreign terrorist organizations, such as al-Qaida or ISIS, but that mechanism requires the group to be foreign-based and cohesive—criteria antifa does not meet. Jason Blazakis, a former director at the State Department’s Counterterrorism Finance and Designations Office, explained, “The group doesn’t meet the first prong of the legal criteria, in that it is not a foreign-based organization. Nor is it an organization that is cohesive. It’s made up of individuals, individual organizations, most of which are primarily based in the U.S.”
Even if the administration were to attempt to create a new executive order for domestic designations, legal experts warn it would almost certainly face constitutional challenges. Patel cautioned that such a move “could result in a legal challenge because there historically haven’t been any inherently domestic groups sanctioned.” The U.S. Constitution’s First Amendment protects freedom of speech and assembly, meaning that labeling a domestic political movement as a terrorist group could infringe on those rights. “It may result in infringement on things like freedom to assemble, freedom of speech—even the Second Amendment could come into play, freedom to bear arms,” Blazakis told NPR.
While the president’s announcement may lack legal teeth, its real-world impact could be significant. As NPR reported, the current push appears to focus more on investigating antifa’s alleged funders than on protest activity itself. Senator Ted Cruz, for example, urged FBI Director Kash Patel to “follow the money,” asserting, “The violence we are seeing is not purely organic…They’ve committed acts of violence all over the country…. I believe there is considerable money funding it.” However, Cruz did not provide evidence to support this claim, and experts warn that broad investigations into groups associated with anti-fascism could sweep up a wide array of civil society organizations, including those involved in community, racial, and social justice work.
Patel warned, “What that means is that there’s potentially a broad array of civil society organizations that can be caught up in this as being potentially linked to anti-fascism in some way or the other. And that would include both groups that are organizing protests, for example … but then also potentially donors and funders who are providing financing for various groups.” She added that this could fundamentally handicap on-the-ground organizations that rely on those funders to do their work.
The FBI and Department of Homeland Security have also been drawn into the fray. While the FBI has warned about violence perpetrated by some antifa adherents, it has made clear that it investigates criminal acts, not ideologies. In 2020, FBI Director Chris Wray described antifa as “a movement or an ideology, not an organization.” He emphasized that the bureau investigates “violent criminal activity” motivated by antifa ideology, but does not target ideology itself. The Department of Homeland Security, for its part, does not officially designate domestic extremist groups as terrorist organizations—again, largely due to First Amendment concerns.
Instead, federal law provides a framework for prosecuting violent acts, not for criminalizing membership in a political movement. As Luke Baumgartner of George Washington University’s Program on Extremism explained to CBS News, “There is no legal mechanism that I’m aware of within U.S. code that would give the president or the federal government the power to declare a domestic ‘group’ as a major terrorist organization or a major terrorist group.” He added, “You can’t prosecute an ideology.”
That’s not to say that individuals associated with antifa or any other movement are beyond the reach of the law. There are numerous federal criminal statutes that can be applied to acts of violence, hate crimes, or terrorism. For example, Dylann Roof and Payton Gendron were prosecuted under hate crime and terrorism-related statutes for their respective mass shootings. Thirty-two states and the District of Columbia also have laws criminalizing acts of domestic terrorism or providing support for such acts.
Federal prosecutors have sought harsher penalties for crimes intended to promote terrorism, such as in cases involving the Proud Boys and Oath Keepers following the January 6 Capitol attack. When former Proud Boys leader Enrique Tarrio was sentenced for his role in the riot, prosecutors succeeded in applying a terrorism enhancement to his sentencing, though the judge did not let it heavily affect the length of his 22-year sentence.
Despite the rhetorical heat, the legal and practical barriers to designating antifa as a terrorist organization remain formidable. As Kenney put it, “Do we as Americans still enjoy the right to free speech, to nonviolent political expression of our views, however unpalatable the Trump administration might find those views? Yes.” The debate, it seems, is far from over—but for now, the law is clear.
