CHANGE: A Crackdown on Islam Is Spreading Across China.

The directive, titled “Reinforcing and Improving Islam Work in the New Situation,” has not been made public. It was issued by the State Council, China’s cabinet, in April of last year and classified as confidential for 20 years.

The directive warns against the “Arabization” of Islamic places, fashions and rituals in China, singling out the influence of Saudi Arabia, the home of Islam’s holiest sites, as a cause for concern.

It prohibits the use of the Islamic financial system. It bars mosques or other private Islamic organizations from organizing kindergartens or after-school programs, and it forbids Arabic-language schools to teach religion or send students abroad to study.

The most visible aspect of the crackdown has been the targeting of mosques built with domes, minarets and other architectural details characteristic of Central Asia or the Arabic world.

Taken in isolation, some of these measures seem limited. Others seem capricious: some mosques with Arabic features have been left untouched, while others nearby have been altered or shut down.

But on a national scale, the trend is clear. Mr. Cui, the poet, calls it the harshest campaign against faith since the end of the Cultural Revolution, when so-called Red Guards unleashed by Mao Zedong destroyed mosques across the country.

The Chinese favor multiculturalism in their adversaries, not at home.