Whatever else it is, this old honor culture has deepened today’s identity politics. Ostracized from the gentile white establishment, many working-class Wyomingites see themselves in these new shows of Trumpian bravado. Like other Americans, they feel a sense of kinship with those who act like them. As Ms. Stubson lamented, “We had never been able to connect to the larger community.” Her husband, Tim Stubson, a former Wyoming representative, admitted that “there was a current there that we were not aware of.”

Honor culture isn’t about just identity, though. This primitive code also seems indispensable to those Republicans radicalized by today’s polarized politics. If one is persuaded that the left is on the verge of destroying American civilization, then electing as many fearless fighters and strongmen as possible is the order of the day. That is why a prominent MAGA donor like Tom Klingenstein said he sees Mr. Trump as “just what the doctor ordered” in “these revolutionary times.”

Enter Harriet Hageman, Mr. Trump’s proxy candidate in his war against Ms. Cheney. A lawyer who once aligned with the old guard, Ms. Hageman broke from Ms. Cheney’s clique to pursue power. Attuned to Wyoming’s new right, her first campaign ad is already appealing to the state’s deeply rooted honor culture. It accuses Ms. Cheney of breaking the “code of the West,” one that requires “loyalty,” “honor” and a willingness to “fight” for compatriots.