On December 7, 2017, a 21-year-old white male posing as a student entered Aztec High School in rural New Mexico and began firing a handgun, killing two students before taking his own life.At the time, the news of the shooting went largely ignored, but the online activity of the alleged killer, William Edward Atchison, bore all the hallmarks of the “alt-right” — the now infamous subculture and political movement consisting of vicious trolls, racist activists, and bitter misogynists.