The tragic killing of political commentator and conservative activist Charlie Kirk has once again put the spotlight on political violence in the United States, with figures on both sides of the political aisle decrying extremism on the other. To understand the danger of political violence today and to find the best solutions for reducing it, it is important to understand the overall threat landscape and how both left- and right-wing violence have evolved and could change in the future. Our analysis of terrorism trends in the United States shows that, indeed, left-wing violence has risen in the last 10 years, particularly since President Donald Trump’s rise to political prominence in 2016, although it has risen from very low levels and remains much lower than historical levels of violence carried out by right-wing and jihadist attackers. More contentious politics in the United States and the expansion of the Make America Great Again (MAGA) movement appear to have reenergized violent left-wing extremists. The left-wing movement as a whole has not returned to its violent heights of the 1960s and 1970s, but 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. Moreover, 2025 marks the first time in more than 30 years that left-wing attacks outnumber those from the far right. Indeed, the increase in left-wing attacks is particularly noticeable because attacks from right-wing perpetrators have sharply declined in 2025. This decline is striking, and explanations are speculative. One possibility is that many traditional grievances that violent right-wing extremists have espoused in the past—opposition to abortion, hostility to immigration, and suspicions of government agencies, among others—are now embraced by President Trump and his administration. Similarly, jihadist attacks have declined in frequency since their peak in the 2010s, owing largely to the destruction of major groups like al Qaeda and the Islamic State and the subsequent decline in the power of the jihadist ideology to inspire attackers. Left-wing attacks are remarkably less lethal overall than jihadist or right-wing attacks. However, even incidents that do not result in mass casualties can still have significant impact. Fortunately, many left-wing attackers (though not all) have demonstrated limited skill in carrying out violence, and the movement is disorganized, with little formal coordination. The rise in left-wing attacks merits increased attention, but the fall in right-wing attacks is probably temporary, and it too requires a government response. In any case, many of the prescriptions for fighting terrorism effectively apply to violence from both the left and right. These include ensuring proper counterterrorism resourcing, avoiding overreactions, and having leadership unequivocally condemn such attacks. The remainder of this brief is divided into six sections. First, terms such as “left-wing” and “terrorism” are defined. Second, trends in left-wing terrorism in the United States are analyzed, with an emphasis on the increase in the number of incidents since 2016. Third, the causes of the rise of left-wing incidents are assessed. Fourth, weaknesses that limit the impact of left-wing terrorism are examined. Fifth, possible reasons for the decline in right-wing and jihadist terrorism are discussed. The sixth and final section discusses several policy implications that can help combat violence from perpetrators across the political spectrum.
Left-Wing Terrorism and Political Violence in the United States: What the Data Tells Us
