The fear about [kids] safety is the least rational. Despite the impression you get from watching crime dramas, children in rich countries are mind-bogglingly safe, so long as they look both ways before crossing the road. Kids in the 1950s—that golden era so often evoked by conservative politicians—were in fact five times likelier to die before the age of five. Yet their parents thought nothing of letting them roam free. In those days, most American children walked or biked to school; now barely 10% do, prevented by jittery parents. Children learn how to handle risks by taking a few, such as climbing trees or taking the train, even if that means scraped knees and seeing the occasional weirdo. Freedom is exhilarating. It also fosters self-reliance.