I need to give Nicholas Confessore and Karen Yourish credit for some of this information.
At the extremes of American life there is replacement theory. It is the notion that Western elites, sometimes manipulated by Jews, want to “replace” and disempower white Americans. The idea of replacement theory is now going mainstream.
Replacement theory, once on hidden message boards and white nationalist sites, has gone mainstream. In has become a potent force in conservative media and politics. The theory has been borrowed and remixed to attract audiences, retweets, and donations.
Mainly, they have become commonplace in the Republican Party. Spoken aloud at congressional hearings, echoed in Republican campaign advertisements, and used by a growing array of right-wing candidates and media personalities.