“So if you care about the foreign victims of immemorial, immoral rituals, you will want to proceed carefully and perhaps learn from history. International humanitarian campaigns don’t have to backfire. It might be useful to look at their notable successes, in fact, and see what swung the balance. Take the late-19th-century campaign against foot-binding in China. The custom began to die out in the first decade of the 20th century. In most places, it happened quickly. The American political scientist Gerry Mackie, an expert on social norms, gives the example of a large group of families in a rural area south of Beijing, in which 99 percent of women born before 1890 had bound feet, and none of the women born after 1919 had bound feet.”