The assassination of conservative activist Charlie Kirk in Utah has thrust political violence back into the national spotlight. Prosecutors have charged 22-year-old Tyler Robinson in the Sept. 10 killing of Kirk as he addressed an audience at Utah Valley University.

Kirk’s assassination is the most high-profile attack yet in what terrorism researchers call a surge in left-wing violence.

A new report from the Center for Strategic and International Studies (CSIS) found that “the number of terrorist incidents involving left-wing extremists so far this year puts 2025 on pace to be the left’s most violent year in more than three decades.” 

For the first time in over 30 years, left-wing attacks and plots outnumber those from the far right. The study tracks 750 terrorist incidents in the U.S. between 1994 and July 2025. 

Leftist posters mocking conservative activist Charlie Kirk’s assassination were taped up at Georgetown University on Thursday before being removed and reported to the FBI. (Fox News)

In March, arsonists set fire to the Republican Party of New Mexico headquarters, leaving behind graffiti that read “ICE = KKK”.

The violence so far has been less lethal than right-wing or jihadist terrorism that dominated past decades. CSIS reports that since 2020, only two people have been killed in left-wing attacks before Kirk’s death: Aaron Danielson in Portland in 2020, and UnitedHealthcare CEO Brian Thompson in 2024. 

One of those was Thompson, who was fatally shot in December 2024. Federal prosecutors allege Luigi Mangione carried out the assassination and charged him with murder, stalking and firearms violations. A judge later threw out terrorism charges, but the Department of Justice has described the case as “politically motivated.”

Charlie Kirk speaks before he is assassinated during Turning Point’s visit to Utah Valley University in Orem, Sept. 10. (Tess Crowley/The Deseret News via AP)

By comparison, right-wing terrorism has caused higher death tolls in recent years. Experts warn that the lull is likely temporary. “Right-wing terrorism could easily return to previous high levels,” the study cautioned.

Researchers urge vigilance in how leaders respond. The CSIS report warns that sweeping crackdowns on nonviolent groups risk fueling more extremism. 

As the report concludes, “U.S. political leaders and activists need to lead by condemning violence on their side and calling for calm when it involves violence on the other side.”

Kirk’s assassination and the Mangione case have shown the nation that left-wing extremists are willing to strike at high-profile conservative figures. 

The frequency of incidents is now higher than at any point since the mid-1990s. Analysts with CSIS say ignoring that trend would be a dangerous mistake.