By Mark Bauerlein (Tarcher/Penguin, 264 pages, $24.95)

It would seem that technology and culture both make the present a good time to be young. The digital tools that are reshaping our economy make more sense to young "digital natives" than to members of older generation, an imbalance of abilities that tips the economic and political scales in favor of young people. Meanwhile, aging boomer parents, rather than pass down a fixed, canonical culture to their kids, encourage a modern-day version of their own rebellion, inviting...