With the cheongsam, fashion in the European sense came to China. In the decades from 1915 to 1950, the cheongsam changed more than women’s costume did in the previous 250 years.

That moment of creativity did not endure. The communist takeover of 1949 restored the ancient practice: a new emperor imposes a new costume. Mao Zedong required his subjects all to wear the same unisex blue suit—and he so desperately impoverished China that few could have chosen otherwise even had they dared. Not until after his death would Chinese women recover any freedom of dress, and not until the 1990s could they afford to exercise that freedom. Today China has overtaken the United States, the European Union, and Japan as the world’s single largest market for luxury goods.

The cheongsam has come rocketing back, too, in a dizzying array of lengths and styles. But the freedom Chinese people have recovered is only a very partial one. The post-Mao rulers of China minutely police any flicker of regional resentment of rule from Beijing. They have by law insisted that the language of the North, known in the West as Mandarin, be recognized as the nation’s sole official language. “Cheongsam” is a Cantonese word for a South Chinese thing—but in almost every media report on the cyberbullying of Kezia Daum, the garment is given its Mandarin name, “qipao."

It’s important to have these details in order to understand what is so deeply sinister about the claims now being made about the prom dress.

Like the idea that audiences should refrain from talking while music is performed, the idea that women should be able to move about as freely and easily as men is a cultural product—popularized by the North Atlantic world in the period after the First World War. If it’s wrong for one culture to borrow from another, then it was wrong to invent the cheongsam in the first place—because not only did the garment’s shape originate outside China, but so, too, did the garment’s purposes. It was precisely because they appreciated that they were importing Western ideas about women that the inventors of the cheongsam adapted a Western shape. They took something foreign and made it something domestic, in a pattern that has repeated itself in endless variations since the Neolithic period.

The policemen of cultural appropriation do not think that way. They have a morality tale to tell, one of Western victimization of non-Western peoples—a victimization so extreme that it is triggered by a Western girl’s purchase of a Chinese dress designed precisely so that Chinese girls could live more like Western girls.

In order to tell that story, the policemen of cultural appropriation must crush and deform much of the truth of cultural history—and in the process demean and infantilize the people they supposedly champion.

Consider, again, the Death Metal Cowboys. Despite their enthusiastic, wholesale adoption of costume and music imported into Botswana, they are unlikely to be accused of cultural appropriation. Why not? The would-be culture police build their whole philosophy on a single assumption of extreme chauvinism: that Western culture is universal—indeed the only universal culture. Western technology, the Western emphasis on individual autonomy and equal human dignity, and even such oddly specific Western practices as death-metal music—the cultural police take all this for granted as thoroughly as a fish takes for granted the water in its fishbowl.