The fastest growing religion in America is—none! One fifth of Americans now list their religion as “none,” up from only 7 percent two decades ago. Among adults under 30, those poised to be the parents of the next generation, fully one third are religiously unaffiliated. Yet these “Nones,” especially parents, still face prejudice in a culture where religion is widely seen as good for your kids. What do Nones believe, and how do they negotiate...