In a move that has ignited fierce debate across the political spectrum and raised profound legal questions, President Donald Trump signed an executive order on September 22, 2025, designating the antifa movement as a domestic terrorist organization. The decision, which the White House says aims to crack down on what it calls left-wing political violence, came less than two weeks after the assassination of conservative activist Charlie Kirk—a killing that has put the nation’s simmering tensions over political extremism back in the spotlight.
Charlie Kirk, a prominent figure in conservative circles and founder of Turning Point USA, was shot and killed on September 10 while giving a speech at Utah Valley University. The accused, 22-year-old technical college student Tyler Robinson, was officially charged with aggravated murder on September 16. Prosecutors have stated their intention to seek the death penalty. Despite the gravity of the crime and the political furor it unleashed, investigators have yet to establish a motive or any connection between Robinson and antifa or other organized groups. As Reuters reported, the suspect is not cooperating with authorities, and no public evidence has surfaced linking antifa to the assassination.
Nevertheless, President Trump has seized on Kirk’s murder as a catalyst for reviving long-standing efforts to target antifa, which he calls a “sick, dangerous, radical left disaster.” At a White House press briefing, spokeswoman Karoline Leavitt declared, “Antifa is going to be designated a domestic terrorist organization. The president intends to sign that executive order very soon, as soon as it’s drafted, as soon as today.” Trump’s executive order, as described by the Australian Associated Press, directs all relevant executive departments and agencies to “investigate, disrupt, and dismantle any and all illegal operations” conducted by antifa or anyone who funds such actions.
But what exactly is antifa, and can it legally be designated as a terrorist organization under U.S. law? That’s where the waters get muddy. According to a 2020 Congressional Research Service report and the Anti-Defamation League, antifa—short for “anti-fascist”—is not a traditional political group. Instead, it’s a decentralized, leaderless movement composed of loose collections of groups, networks, and individuals. Some adherents cluster into “affinity groups” of three to eight people who coordinate at protests or share resources, often communicating via encrypted messaging apps. The movement’s roots trace back to early 20th-century European anti-fascist activism, but it gained new prominence in the U.S. following Trump’s 2016 election.
Antifa activists are known for embracing “direct action,” which can range from peaceful protest to confrontational tactics such as vandalism or, in rare cases, violence. They often wear black clothing and masks, a style sometimes called “black bloc,” to protect their identities. Online, they may track or dox individuals they view as right-wing extremists. However, as the Anti-Defamation League notes, “While some extreme actors who claim to be affiliated with antifa do engage in violence or vandalism at rallies and events, this is not the norm.”
Despite the rhetoric, U.S. law enforcement agencies have never officially connected antifa to a terrorist incident. The most notorious episode involving an individual claiming antifa affiliation occurred in Portland, Oregon, in August 2020, when Michael Reinoehl shot and killed Aaron “Jay” Danielson, a member of the far-right group Patriot Prayer. Reinoehl was later killed by law enforcement during an attempt to arrest him. More recently, a San Diego jury found two men guilty of conspiracy to riot earlier this year in a case stemming from 2021 protests where prosecutors labeled the men as antifa members.
Trump’s executive order, according to Reuters and the Associated Press, seeks to unlock expansive new investigative and surveillance powers for federal agencies. A Justice Department official told Reuters that the designation would allow the government to more closely track the finances and movements of U.S. citizens believed to be linked to antifa, as well as to investigate any foreign funding. The FBI’s Counterterrorism and Counterintelligence Divisions are expected to spearhead these efforts, focusing on both domestic and international sources of support.
Yet the legal foundations for such a move are, at best, shaky. As The Guardian and UNN report, there is no legal mechanism in the United States to designate domestic groups as terrorist organizations—unlike the process for foreign groups such as ISIS. The First Amendment’s protections for free speech and association make it constitutionally dubious to criminalize adherence to an ideology, no matter how radical. Heidi Beirich, co-founder of the Global Project Against Hate and Extremism, told UNN, “The move was absurd from the start and has no legal or factual basis.” She added, “There is a mechanism for designating foreign organizations as terrorist, and then legal levers can be applied, including a ban on material support. But at the domestic level, there is no such mechanism, and there is no clear way to apply this to antifa.”
Former FBI Director Christopher Wray and other extremism experts have echoed this view, consistently characterizing antifa as a movement or ideology, not an organization that can be formally declared terrorist. During Trump’s first administration, at least two attempts were made to designate antifa as a terrorist organization, including during the 2020 George Floyd protests, but both efforts failed for lack of legal authority.
Critics warn that the new executive order could have chilling effects on free speech and political dissent. “The big picture focus is on foreign money seeding U.S. politics and drawing connections to foreign bank accounts,” a White House source told Reuters. “The designation of antifa gives us the authority to subpoena banks, look at wire transfers, foreign and domestic sources of funding, that kind of thing.” But legal experts caution that, without new legislation or a dramatic reinterpretation of existing law, the executive order’s practical impact may be more symbolic than substantive. As Beirich put it, unless “Trump invents some extra-legal mechanism that I can’t even imagine,” the order is unlikely to withstand legal scrutiny.
Meanwhile, federal law enforcement already investigates violent and organized crime associated with a variety of hate groups and ideological movements, regardless of their political orientation. Political violence experts and U.S. law enforcement officials have previously identified far-right attacks as the leading source of domestic violent extremism. Still, Trump administration officials have, since Kirk’s death, sought to portray left-wing groups as the primary drivers of such violence.
As the nation grapples with the aftershocks of Charlie Kirk’s assassination and the broader implications of Trump’s executive order, the debate over how to define, confront, and regulate political extremism in America is far from settled. With legal challenges looming and deep divisions over the nature of antifa itself, the coming months are sure to test the boundaries of executive power, constitutional rights, and the nation’s commitment to free expression.
