President Trump on Monday signed an order designating the anti-fascist movement antifa as a domestic terrorist organization, following through on a pledge in the wake of the killing of Charlie Kirk to crack down on left-wing groups.

The order designates antifa as a “domestic terrorist organization.” It gives government agencies a broad mandate to investigate any operations conducted by antifa or for any operation where an antifa member “provided material support.”

The order alleges antifa uses “illegal means to organize and execute a campaign of violence and terrorism nationwide” to accomplish its goals of overthrowing the government and law enforcement.

“Individuals associated with and acting on behalf of Antifa further coordinate with other organizations and entities for the purpose of spreading, fomenting, and advancing political violence and suppressing lawful political speech,” the order states. “This organized effort designed to achieve policy objectives by coercion and intimidation is domestic terrorism.”

Trump’s order is sure to prompt questions and criticism about its legality and its implementation. Experts have said antifa is a decentralized ideology without a clear leadership structure, raising concerns about whether the order will be used to broadly crack down on left-wing organizations.

It is also unclear what authority Trump has to designate a domestic terrorism organization, and his attempt to do so may draw legal challenges.

In the wake of the political assassination of Kirk, the conservative activist and founder of Turning Point USA, Trump and other White House officials have pledged to crack down on left-wing groups that they claim have fomented violence in the United States.

Vice President Vance has said the administration will look at cutting off funding for left-wing groups, and Trump has focused particularly on antifa. 

Republicans have blamed antifa activists for rioting in major cities after the murder of George Floyd in 2020, and the term has been more broadly applied to left-wing protesters across the country.