Donald Trump gestures to the crowd as sons Eric Trump and Donald Trump Jr. look on near the exit, during a campaign rally at J.S. Dorton Arena in Raleigh, North Carolina, U.S., November 4, 2024. REUTERS/Brian Snyder

In a fiery declaration, President Donald Trump announced he is designating "antifa" a terrorist organization. Some experts say he lacks the authority to do so and will struggle to enforce such a move — while others warn it could give him sweeping license to target groups or individuals he disfavors.

“I am pleased to inform our many U.S.A. Patriots that I am designating ANTIFA, A SICK, DANGEROUS, RADICAL LEFT DISASTER, AS A MAJOR TERRORIST ORGANIZATION,” Trump wrote on social media on Wednesday evening. “I will also be strongly recommending that those funding ANTIFA be thoroughly investigated in accordance with the highest legal standards and practices. Thank you for your attention to this matter!”

As many have noted, antifa is not an organized group. It simply means “anti-fascist,” or “anti-fascism.”

But Trump has taken the step anyway. Here’s what some experts say.

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BBC News reports that some legal experts have called into question Trump’s legal authority to declare antifa a terrorist organization.

“The existing rules do allow the government, specifically the State Department, to make a list of ‘foreign terrorist organizations’ which makes it a crime to give funds or other ‘material support’ to those groups.”

“But the key word here is ‘foreign,'” BBC notes, “and those experts we have spoken to pointed out that free speech rights under the US constitution’s first amendment would limit Trump’s ability to ban – or restrict funding for – domestic movements like antifa.”

Rumen Cholakov, an expert in US constitutional law at King’s College London, “told us that if the government were to use its powers against them in the US their actions would be ‘potentially susceptible to constitutional challenges’ in court for violating these rights.”

Professor David Schanzer, director of the Triangle Center on Terrorism and Homeland Security at Duke University, told BBC Verify, “Under the First Amendment, no one can be punished for joining a group or giving money to a group.”

Meanwhile, other experts have also weighed in.

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Attorney and MeidasTouch editor-in-chief Ron Filipkowski observed, “Since antifa is now designed as a terrorist organization it will be interesting to see how they determine who is a member and how they prove it is an organization.”

Politico senior legal affairs correspondent Kyle Cheney noted, “Trump says he’s designating ‘antifa’ a terrorist group and launching a probe into finding of antifa activities. The FBI has long said antifa doesn’t really have a centralized structure or leadership.”

U.S. Rep. Daniel Goldman (D-NY), an attorney, told CNN Wednesday night that “there is no antifa organization.”

He added, “the point” is that Trump is “using the Charlie Kirk murder as a pretext to go after people that he disagrees with. He, on the very night of Kirk’s murder, you will remember, accused the left of committing the murder — when the murderer had not even been caught or identified. This is all a pretext, and it’s a shame, I think … that Charlie Kirk actually stood for free speech. And instead, they’re using his memory to attack free speech.”

Political scholar Dr. Michael Mackey issued this warning: “‘Antifa’ is an artifact of Russian information warfare and the Kremlin-sponsored MAGA cult. No such entity exists in American civil society. Trump is owned by Putin.”

Intelligence and foreign policy analyst Malcolm Nance, a terrorism expert, said, “You cannot designate an idea as a terrorist group.There is no organization called ANTIFA. There is no leadership or funding path. There is no membership.”

“What he is doing is setting the stage to designate ANY American as a terrorist,” Nance alleged. “That’s Fascism.”

CBS News national security coordinating producer Jim LaPorta, an award-winning journalist, wrote: “It’s unclear how Pres. Trump could designate a group inside the U.S. as a domestic terrorist group. The U.S. does not have a federal crime of domestic terrorism. Additionally, it’s been understood that the Govt. would run into 1st and 4th Amendment issues.”

But those hurdles aside, experts are still issuing warnings.

Olga Lautman, a Senior Fellow at the Center for European Policy Analysis (CEPA), an expert on Russia, and creator and co-host of the Kremlin File podcast series, expressed concern.

“So Trump is designating antifa as a terrorist organization,” she wrote. “Problem is he thinks all Democrats are this so called antifa. He is following Russia’s playbook step by step to crush opposition. Hope everyone wakes up.”

On Substack, Lautman expanded her warning.

She pointed to White House Deputy Chief of Staff Stephen Miller’s remarks on Monday, after the assassination of Charlie Kirk.

Calling the “radical left” a “vast domestic terror movement,” Miller said: “With God as my witness, we are going to use every resource we have at the Department of Justice, Homeland Security and throughout this government to identify, disrupt, dismantle and destroy these networks and make America safe again for the American people.”

“It will happen, and we will do it in Charlie’s name,” he vowed.

“Where have I heard this before?” Lautman said of Miller’s statement. “In Russia, where the Kremlin seizes upon every terrorist attack, bombing, protest, or act of violence (some of which they carry out in false flag operations) to justify new crackdowns, laws, and the systematic destruction of any semblance of independent opposition.”

Lautman continued her stark warning, writing, “what makes the current moment in America so perilous is how closely it now echoes this Soviet/Russian script, with the killing of Charlie Kirk already being transformed from an individual crime into the cornerstone of a supposed vast conspiracy of leftist violence — again, without evidence — a pretext for sweeping crackdowns that will not stop at violent actors but extend to protesters, grassroots organizers, and the infrastructure that sustains them.”

“Groups like Indivisible and MoveOn, platforms like ActBlue, that fund Democratic candidates,” she predicted, “will all be recast as pipelines of extremism, stripped of their democratic role.”