Glenn Beck looks like the dad in a Disney movie. He’s earnest, geeky, pink, and slightly bulbous. His idea of salty language is bullcrap. The atmosphere at Beck’s Mercury Studios, outside Dallas, is similarly soothing, provided you ignore the references to genocide and civilizational collapse. In October, when most commentators considered a Donald Trump presidency a remote possibility, I followed audience members onto the set of The Glenn Beck Program, which airs on Beck’s website, theblaze.com. On the way, we passed through a life-size replica of the Oval Office as it might look if inhabited by a President Beck, complete...