This seems like a good spot to recommend Roberts Evans Behind the Bastards: How Conservatism Won. in which “Robert sits down with David Bell to discuss how a consortium of rich failsons got together to fund a network of right wing think tanks and shift American culture in a fun new direction. (note: it was not actually fun at all).” It’s a bit long but is very informative.
tl;dr the rich hated FDRs New Deal and immediately set about undoing everything it touched, they want a return to the gilded age with themselves as the robber barons and gentry and everyone else as a subservient underclass