The latest online craze in China is short videos — 10- or 15-second snippets, whimsical, artistic and otherwise, made and distributed with increasing creativity and popularity. China's massive censorship machine is not far behind. The authorities issued two rules on Jan. 9 that identify some 100 categories of banned content and demand that short-video platforms review all content before it is posted. The strictures are yet another reminder of the power and sweep behind China's attempts to police the internet.

The short-video craze took off over the past year or so among young people. According to CNBC, the short videos are usually packed "with music and special effects ... fun and quirky for both their makers and viewers." One app, Douyin, had more than 150 million daily active users as of June.

China, which boasts some 800 million internet users, subjects them to the world's largest censorship operation, including the Great Firewall that blocks thousands of foreign websites from being accessed inside the country. Censors also police all kinds of digital activity, and the demands sent to the short-video platforms offer a glimpse of how it works.

The platforms were instructed to scrub any content from videos that might "ridicule, satirize, oppose, or defame the socialist road with Chinese characteristics," and its "theory, system and culture," as well as "weaken, deviate, attack, or vilify the leadership of the Communist Party of China," or touch on the sensitive issues of independence in Taiwan, Hong Kong, Xinjiang or Tibet, "including video materials, works, speech, pictures, words, reactionary flags, slogans" and more. In other words, short videos must do nothing to harm the ruling party-state, as well as its priorities or policies.

On a much larger scale, China is marshaling artificial intelligence and big-data techniques to exert even greater control over its population. Xiao Qiang, director of the Counter-Power Lab at the University of California at Berkeley's School of Information, writes in the January issue of the Journal of Democracy that a new generation of digital technology is being used to collect information in China — from facial and voice recognition to DNA records and a ubiquitous network of surveillance cameras. Eventually, knitting it all together could allow the state "to identify and quash opposition in advance." Xiao says the party-state may be building a "responsive tyranny," or a "digital totalitarian state," which he concludes will be "a nightmare for Chinese citizens and for those all over the world who value human freedom."