Righteous rage constitutes an expression of political power for many hate groups operating currently in the United States, enticing them toward emotionally charged aggression against their adversaries. We offer a case study of one such group—the Proud Boys—in the context of their violent attack of the U.S. Capitol on January 6, 2021. Rather than a momentary feeling, their righteous rage is a potent force for forming, defining, and organizing their mission to overpower their adversaries. In particular, their righteous rage is defined by (a) behavioral manifestations, (b) the emotional contagious impact of such manifestations, and (c) the centrality of raging to one’s identity as a social movement. Regarding their identity, they tend to don Proud Boy symbols on their clothes, wear helmets, and carry lethal weapons, as if aspiring to exhibit the warrior’s bravery, valor, strength, and devotion. The Proud Boys members self-position as warriors protecting the nation, Western chauvinism and (more recently) the White race. In raging righteously, the Proud Boys are absorbed with evildoers, seeking to expose their malicious past and attempting to subvert their current designs. With such absorption, the emotionally charged rationale for aggression is set in place.