I could see that. And often, stats are presented for ideological reasons. I have only been following this New America data for a couple years, and you should check out their “about” sections or scroll to the bottom to see who’s pulling the information together and their credibility (CNN’s Peter Bergen). Of course 9/11 skews every metric for terror killings on U.S. soil. Yet, I think in the era of “never forget” that no one really forgot 9/11. I don’t see New America as “ideological” in their assessments, they just want to give context for comparing right-wing apples to jihadist oranges (with left-wing apricots thrown in for good measure).
To check my own bias, I would accept a death rate study on “lethal outcomes in the nuclear age” SINCE Hiroshima and Nagasaki to assess the risk of keeping nuclear energy and bombs in this world. (This would include Chernobyl meltdowns, submarine accidents, and so forth, but obviously no nuclear explosions on major cities, which only the United States has done twice in 1945.) But again, anything is possible in the future — so all “worst outcome” considerations should be considered, too, for governments and citizens alike.