Which specific right-wing extremist groups have been linked to the most fatalities in the USA between 2015 and 2024?

1. Summary of the results

Between 2015 and 2024, multiple independent analyses converge on a central finding: right‑wing extremist actors account for the majority of domestic‑terrorism fatalities in the United States, with several high‑casualty events driving much of the total (examples repeatedly cited include Charleston 2015, Pittsburgh Tree of Life 2018, and El Paso 2019) ^{[1] [2] [3]}. Quantitative summaries in the provided material place right‑wing responsibility for roughly three‑quarters or more of domestic‑terror deaths since 2001, and that pattern persists in the 2015–2024 window where documented incidents attributed to right‑wing motivations produced the largest single‑event fatality counts ^{[3] [1]}. These sources treat individual attackers and movements on the ideological right as the principal contributors to lethality across the decade ^{[1] [3]}.

2. Missing context/alternative viewpoints

The supplied analyses note important omissions that affect attribution: many datasets classify attacks by motive, target, or claimed affiliation, and definitions vary, so counts depend on methodology ^{[4] [3]}. Some sources point out rising left‑wing violence in 2025 and emphasize that left‑wing incidents are generally less lethal than right‑wing or jihadist attacks, which complicates trend narratives if the temporal window shifts ^{[5] [4]}. Also, several summaries do not disaggregate organized groups from lone‑actor perpetrators or from loosely networked movements; as a result, fatalities attributed to “right‑wing extremist” actors may reflect a small number of high‑fatality lone attackers rather than sustained group campaigns ^[3].

3. Potential misinformation/bias in the original statement

Framing the question as “Which specific right‑wing extremist groups have been linked to the most fatalities” risks implying organized groups are the primary drivers, when multiple sources show high fatalities often stem from lone actors inspired by right‑wing ideologies rather than formal group hierarchies ^{[1] [3]}. Political actors or outlets emphasizing a party or movement could benefit from attributing deaths to named groups rather than individuals, shaping public perception of organized threat levels ^[3]. Conversely, actors seeking to minimize the scale of right‑wing violence may emphasize definitional ambiguities or compare long‑term baselines ^[4]. The evidence in the provided analyses supports a factual claim about the predominance of right‑wing‑motivated fatalities, but specific group attribution requires careful methodological transparency about classification, lone‑actor versus group status, and time windows ^{[2] [5]}.