A White House vow to dismantle left-wing organizations may be easier issued than implemented, according to experts.

“There’s not a lot of federal law on this,” stated Scott Walter, president of the Capital Research Center, a nonprofit based in Washington focused on tracking progressive groups and holding influence in conservative circles. “Frankly, states and local communities should improve their prosecution of criminal activity, similar to what was seen in the 1960s. They possess significantly more resources.”

Walter’s statement reflects the difficulty that administration officials face as they attempt to address the outrage following the Sept. 10 assassination of prominent conservative activist Charlie Kirk with tangible actions.

Key White House figures, including President Donald Trump, Vice President JD Vance, and deputy chief of staff Stephen Miller, have accused left-wing groups of instigating political violence following the assassination, which deeply unsettled the nation and left Trump’s MAGA supporters feeling a blend of grief, fear, and anger.

In response to inquiries about plans to focus on such organizations, a White House spokesperson provided clips of a Trump interview on Fox News, where he accused leftist groups of “incitement to riot.”

On Wednesday, Trump announced that he had labeled antifa, a loose coalition of extreme left-wing groups, as a “major terrorist organization.” However, federal law does not have a domestic equivalent to a “foreign terrorist organization”—a designation used to sanction non-state American adversaries abroad.

“He can say what he wants, but it has no legal significance,” commented Mary McCord, a former top national security official at the Justice Department. “Creating a designation process for domestic organizations that would have legal consequences requires Congress to establish a statute for that process. Theoretically, he could attempt this through executive orders, but it would not activate any current charges related to material support for foreign terrorist organizations.”

Trump made a similar proclamation about antifa during his first term in office, and former Attorney General William Barr asked the FBI to develop a strategy to investigate left-wing organizations. That led the FBI to enlist members of the far-right group the Proud Boys as confidential human sources, some of whom later entered the Capitol during the Jan. 6, 2021, attack.

In January, Rep. Marjorie Taylor Greene, R-Ga., proposed labeling antifa a terrorist organization. But her House resolution, which has not advanced, would not have the force of law. Greene did not reply to a text message seeking comment.

Authorities have not publicly identified any link between antifa and Kirk’s death. When Utah prosecutors charged Tyler Robinson with murdering Kirk, the documents they filed in court this week did not identify him as a member of any group.

In 2020, then-FBI Director Christopher Wray said that while antifa was “a real thing,” it was “not a group or an organization. It’s a movement or an ideology.”

Jon Lewis, a research fellow at the Program on Extremism at George Washington University, said: “It’s fairly obvious and there’s a general consensus in the research community that antifa is not an organization, lacks any coherent membership structure, and most importantly it’s not foreign. In a period where there is significant political violence, there is at least increased concern around putting a target on the back of anyone who can be tarred with the brush of being antifa.”

Despite the claims of prominent allies of the president, Lewis pointed out that studies show that right-wing violence is a much deadlier threat in recent history than left-wing violence.

Federal authorities may probe groups they suspect have spurred riots and attacks on law enforcement officers, groups that illegally make personal information public or groups that are responsible for “drop points for weapons and material,” according to an administration official. That could result in more prosecutions under existing laws, but Congress would still have to act to make a wider range of activity illegal.

White House officials and outside groups appear to have homed in on a still-developing plan to target the tax-exempt status of groups that fund liberal activism, including the Open Society Foundations, which was founded by billionaire George Soros, and the Ford Foundation.

“Do you know they benefit from generous treatment? They are literally subsidized by you and me, the American taxpayer,” Vance said when he guest-hosted “The Charlie Kirk Show” on Monday. “And how do they reward us? By setting fire to the house built by the American family over 250 years.”

Federal law prohibits the president and the vice president from ordering investigations into organizations’ tax status.

In 2017, during Trump’s first term, the Justice Department settled a lawsuit with conservative groups that claimed they had been unfairly put under an IRS microscope when they applied for tax exemptions when Barack Obama, a Democrat, was president.

Trump’s rhetoric has sent a chill through the liberal political sphere, activists said.

Angelo Greco, a progressive operative who advises groups that have not been mentioned by Trump — including Our Revolution, One Fair Wage, Reproductive Freedom for All and Black Women’s Roundtable — said past threats from administration officials to go after liberal nonprofit groups have given them time to prepare.

“What’s different now is that I didn’t think the temperature could reach a boiling point, but we’re there,” Greco said.

Left-leaning advocacy groups are rethinking contingency plans, including “changing their name, revising their mission or operating differently,” he said.

Joseph Geevarghese, the executive director of Our Revolution, a group founded by Sen. Bernie Sanders, I-Vt., after his 2016 presidential campaign that is focused on electing progressive lawmakers and advancing left-wing economic causes, said it’s still far too soon to know how the promised crackdown would affect progressive advocacy organizations.

He said his organization was less likely to be hampered by the effort, though, because it does not rely on any major donors and it is focused on economic issues rather than cultural touch points.

Geevarghese said he has heard from some grassroots activists that there is increased concern about taking part in protests or other group action. But he said: “We’re going to continue doing what we do.”

Walter, the president of the Capital Research Center, whose group has briefed the White House on nonprofit organizations’ voter registration efforts that it sees as partisan, said that despite the challenges, he is hopeful that the administration can take effective actions against left-wing groups.

“I’m more optimistic than I’ve ever been, but it is definitely an uphill battle to make progress,” he said.

To do that, he added, the White House should focus on sources of funding, including tax exemptions.

“I hope the administration will come up with serious strategic ways of dealing with these things,” he said. “The larger problem, namely all the radicalization, needs to be looked at strategically.”