"Part memoir, part historical and social analysis, J. D. Vance's Hillbilly Elegy is a fascinating consideration of class, culture, and the American dream. Vance's grandparents were "dirt poor and in love." They got married and moved north from Kentucky to Ohio in the hopes of escaping the dreadful poverty around them. Their grandchild (the author) graduated from Yale Law School, a conventional marker of their success in achieving upward mobility for...