Vincent L. Anderson ยท Oct 19, 2026
1. Framework and scope
The framework, presumed. This essay presumes the two earlier documents: "The Diagnostic Advantage of Moral Anti-Realism" and its application to five ideologies. It takes as given three positions: moral anti-realism, impartial altruism as the overriding aim, and Sapolskian determinism. It also takes as given the paper's account of hostility as a pipeline: sentiment comes first, moralization recruits disgust and outrage, conflict manufactures felt objectivity, conviction drives intolerance and violence, and networks reward and return the output. Institutions that must codify sentiment state it as desert. The application added two further findings. Extremity is a property of how an ideology is held and enacted. And every ideology attributes free will selectively: determinism where it excuses, free will where it blames.
What the framework asks of terrorism. On these presumptions, an attack is not a free act of evil to be avenged. It is the output of a causal system, with the attacker as one node. The diagnostic question is therefore not "who deserves what?" but "which causes produced this, which amplified it, and which can be changed?" The aim is to reduce the suffering such attacks cause, including the suffering caused by responses to them.
Definitions. Two definitions are used, because the major datasets differ. Cato's 1975โ 2025 dataset counts premeditated, ideologically motivated killings by non-state actors, and excludes spontaneous hate crimes (Nowrasteh 2026). CSIS counts "the deliberate use or threat of premeditated violence by nonstate actors" for political goals and broad psychological impact, including plots and non-lethal attacks (Byman and McCabe 2025). "Domestic" here means attacks on U.S. soil by people living in the United States, whatever the ideology, including homegrown jihadists. The 9/11 attacks were planned and staffed from abroad and are excluded.
Case selection. Cases were chosen on two criteria the request named. Most destructive: the highest death tolls. High-profile: attacks whose political effects reached far beyond their death tolls, such as assassinations. Historical racial terror is included, because by death toll it dwarfs the modern record.
2. The record
The modern totals. From 1975 to 2025, 208 attackers killed 3,577 people on U.S. soil in politically motivated attacks, about 0.35% of all U.S. murders (Nowrasteh 2026). Two attacks, 9/11 and Oklahoma City, account for about 88% of those deaths. Excluding both, 186 killers took 430 lives: 45% by right-wing attackers, about 32% by Islamist attackers and about 16% by left-wing attackers. CSIS's count for the past decade gives 112 victims of right-wing attacks, 82 of jihadist attacks and 13 of left-wing attacks. CSIS also found that in the first half of 2025, left-wing incidents (attacks and plots) outnumbered right-wing ones for the first time in more than 30 years, five to one. The numbers are small, and left-wing attacks remain far less lethal. CSIS's data run from 1994 to 4 July 2025 (Byman and McCabe 2025).