In 2001’s The Metaphysical Club, Menand worked a group biography into a history of American pragmatism. In this essay collection, he devotes his agile mind mainly to 20th-century politics and culture. His intellectualism coexists with offhand irreverence. He can broaden pointed arguments to enlightening effect such that a fresh assessment of Pauline Kael becomes a look at the booby traps of pop criticism. And he’s ready with incisive quips; a piece on the ’60s counterculture begins: ”If you advised a college student today to tune in, turn on, and drop out, she would probably call campus security.” Taking ideas apart to show you how they work (or fail to), Menand fashions edifying entertainment.