In 1929, the Church of Scotland Mission, which had a long and successful history of missionary work among the Kikuyu in colonial Kenya, began a campaign to eradicate the practice of female circumcision. The results were hardly what church members hoped for. Large numbers of Kikuyu left the church, and Kenya’s leading anticolonial political organization mounted a vigorous attack on the church’s policies. Female circumcision became a nationalist issue, and a custom that might have gradually disappeared grew further entrenched. Nearly 40 percent of Kenyan women today are estimated to have undergone some form of it.

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 […]