Overview

• CSIS analyzed 750 attacks and plots from 1994 to July 4, 2025 using a terrorism definition focused on nonstate political violence intended to influence a broad population.
• The analysis finds left-wing terrorism has risen since 2016, and 2025 is the first year in more than three decades when left-wing incidents outnumber far-right ones.
• Right-wing incidents dropped sharply in early 2025, with CSIS counting only one case in the first half of the year: the June assassination of Minnesota legislator Melissa Hortman and her husband.
• Over the past decade, CSIS tallied 36 left-wing attacks causing 13 deaths versus 152 right-wing attacks causing 112 deaths, underscoring differing frequency and lethality.
• The Atlantic notes challenges in coding ideology, while right-leaning outlets amplify the findings and point to Charlie Kirk’s Sept. 10 killing—allegedly by a suspect with left-leaning motives—which is not included in the CSIS counts.