Communion: Finding My Way Back to FaithBy JD VanceHarper, 295 pages, $35In 2016, JD Vance’s Hillbilly Elegy, a memoir of ascent from Appalachia to Yale Law, became the definitive professional-class explainer on Trumpism. This summer, Vance’s follow-up memoir has him finding his way from Yale back to religious faith and a few other middle-American things, such as distrust of elite prescriptions for personal and societal flourishing. An apologia f…