A group of Uyghur friends are having a late-night chat. “I wish the Chinese would just conquer the world,” one says suddenly. “Why do you say that?” another asks, surprised. “The world doesn’t care what happens to us,” the first man replies. “Since we can’t have freedom anyway, let the whole world taste subjugation. Then we would all be the same. We wouldn’t be alone in our suffering.” It is an understandable outburst of bitterness. The Uyghurs are a Muslim minority who live mainly in China’s north-western Xinjiang region. They have long faced discrimination and persecution. Since 2016, the repression...