Students take part in an anti-government rally in Hong Kong.(Chris McGrath/Getty Images)

A search for “#hongkong” on Twitter reveals a vast visual patchwork of the city’s unavoidable protests, including pro-China agitprop, sympathetic memes and imagery from the hundreds of thousands of pro-democracy marchers who have braved police crackdowns.

But the same searches for Hong Kong on TikTok, the short-video app from a Beijing-based tech giant that has gone viral in the U.S., reveal a remarkably different — and, for the Chinese government, more politically convenient — version of reality: playful selfies, food photos and singalongs, with barely a hint of unrest in sight.

TikTok has quickly become one of America’s most popular mobile apps, a flashy, frenetic, video playground beloved by teens and downloaded more than 110 million times across the U.S. With its blend of goofy memes, fast-twitch skits and chart-topping earworms like “Old Town Road,” the app has quickly become China’s most successful social-media export abroad and a global phenomenon, installed by 1.3 billion users around the world.

Celebrities are also flocking to the app, including New England Patriots quarterback Tom Brady, whose first video post — a season-opener supercut posted Tuesday, set to rapper Young Thug’s “Hot” — coincided with TikTok’s new multiyear marketing deal with the NFL. TikTok has ranked among the world’s most-downloaded apps for the last 18 months, according to data provided by the research firm Sensor Tower. U.S. viewers have spent more than $37 million over the last two years on virtual coins for their favorite creators, TikTok’s primary way of making money.

But researchers have grown worried that the app could also prove to be one of China’s most effective weapons in the global information war, bringing Chinese-style censorship to mainstream U.S. audiences and shaping how they understand real-world events. Compounding researchers’ concerns are TikTok’s limited public comments about the content it removes and its purported independence from censors in Beijing.

TikTok’s parent company ByteDance said in a statement that U.S. user data is stored domestically and that the app’s content and moderation policies in the U.S. are led by a U.S.-based team not influenced by the Chinese government. ByteDance repeatedly declined to make executives available for on-the-record interviews.

In its statement, the company defended TikTok as a place for entertainment, not politics, and said its audience gravitates there for positive and joyful content as a possible explanation for why so few videos relate to sensitive topics such as the protests in Hong Kong.

The company declined to provide details of how the app is policed in the U.S. or how the U.S. team shields itself from being influenced by authorities in Beijing, where ByteDance is headquartered. Officials in the Chinese embassy did not respond to requests for comment.

TikTok’s surging popularity spotlights the tension between the Web’s global powers: the United States, where free speech and competing ideologies are held as (sometimes messy) societal bedrocks, and China, where political criticism is forbidden as troublemaking.

TikTok’s Chinese counterpart, researchers say, remains captive to the ruling regime’s ideas of appropriate content and censorship, and they point to the way the nation’s Communist Party has used it as a propaganda vessel for young audiences that might otherwise not seek out state-media news.

Yaqiu Wang, a Hong Kong-based researcher for Human Rights Watch, said the Hong Kong protests marked one of the first big tests of how Chinese companies could project the government’s dogmas to a global audience.

“They are making the commercial media repost or reproduce what has been produced by state media. And they are forcing censorship to create a narrative in the sense that this is not what happened,” Wang said. “For Chinese companies, the government has so much control. You have no choice. If it’s politically sensitive, your company is in jeopardy.”

Long seen as a launchpad for viral memes, TikTok in the U.S. is entering a kind of social-media adolescence, expanding into a new public square for young viewers to learn about and riff off current events. Videos with the #trump2020 hashtag, for instance, have accrued more than 70 million views: One clip by user CountryGirl9352, in which she lip-syncs Trump’s complaint about plastic straws, has received more than 500 comments and 10,000 likes.

It’s impossible to know what videos are censored on TikTok: ByteDance’s decisions about the content it surfaces or censors are largely opaque. The company provides no information about the videos it removes for violating its prohibitions against hate speech or extremism, and it does not offer the kinds of tools that would make the platform accessible to outside research. It’s also possible that users in Hong Kong could be self-censoring by not posting politically fraught content onto an app closely scrutinized by Chinese censors.

But popular hashtags used by Hong Kong protester that have spread widely across other social media barely exist on TikTok.

The #antielab hashtag, a central organizing post named for protesters’ resistance to an extradition bill seen as weakening Hong Kong sovereignty, has more than 34,000 posts on Instagram but only 11 posts on TikTok, totaling about 3,000 views. The hashtags for #HongKongProtests and #HongKongProtestors, some of the biggest rallying points on Twitter, return either a single video or an error message: “Couldn’t find this hashtag: Check out trending videos.” The #HongKongProtest hashtag showed six videos, totaling about 5,000 views.

Searches on the TikTok app in the U.S. using Chinese characters produce similar results. A main protest hashtag (反送中), used to refer to the anti-extradition movement, shows about 100 videos totaling roughly 105,000 views. For comparison, a hashtag for #snails on TikTok has more than 6.6 million views.

TikTok’s parent company has offered limited information about its mix of human and algorithmic censors, which scan videos and remove blacklisted words and images. The company’s chief said last year it would employ 10,000 moderators to flag and remove content following a crackdown from Chinese regulators targeting the app’s “improper content.”

That lack of transparency, alongside the company’s Chinese roots, appears to have become a point of satire for some TikTok users. The #TiananmenSquare hashtag — named for the sprawling Beijing center where military forces in 1989 killed thousands of people following pro-democracy protests, a massacre strictly censored across China — shows about 20 videos, most of which joked that the bloody episode never happened.

Organized online Chinese campaigns to disparage Hong Kong protesters, researchers said, also suggest that ByteDance could be used to influence global perceptions. Facebook, Twitter and YouTube last month said they had removed fake accounts, including some disguised as everyday Americans, that had praised the government and portrayed the protesters as terrorists and cockroaches.

“If they’re willing to do this on Twitter and Facebook, of course they’re going to want to do it on their own platform,” said Elliott Zaagman, a writer and co-host of a popular podcast on the Chinese tech industry.

Despite TikTok’s growing popularity in the U.S., the app has barely registered in Washington’s ruling circles. Many lawmakers perhaps first heard of the company when a Facebook executive pointed to its rise at a hearing this year as evidence that Facebook didn’t hold a monopoly on people’s attention spans online.

In February, the Federal Trade Commission fined the company $5.7 million over allegations it violated rules meant to protect kids’ privacy online. FTC watchdogs said that the precursor to TikTok, the karaoke app Musical.ly, illegally collected names, email addresses, pictures and other data from children younger than 13.

ByteDance has since sought to introduce itself to regulators, registering its first lobbyist in June and hiring additional outside consultants a month later, federal ethics filings show.

ByteDance has been named the world’s most valuable start-up thanks to massive investments from tech powerhouses such as Japan’s SoftBank Group that have valued it at more than $75 billion. (Uber, for comparison, is worth less than $60 billion.)

Founded in 2012, ByteDance now owns a stable of news, video and selfie apps, most of which are used almost exclusively in China. But in Silicon Valley, TikTok is regarded as having traced a uniquely enviable rise, becoming the first Chinese app to truly pierce the global Internet mainstream.

TikTok closely resembles its Chinese counterpart, Douyin, which ByteDance makes available only to audiences in mainland China. The app has become one of the most popular conduits of news and entertainment in the world’s second-largest economy, and it has been celebrated in state media as a homegrown success story well-suited to disseminate the government’s ideology.

State-endorsed propaganda is commonplace, said Zaagman, who compared it to the hidden medicine in a dog’s food bowl: a heap of fun videos that make it easier to swallow a dash of nationalism.

ByteDance must comply with China’s “Great Firewall,” which blocks major news sources and censors what the party regards as objectionable facts and ideas. Social-media platforms in China are required by law to purge political dissent, and TikTok’s Chinese counterpart has banned a broad range of supposedly subversive topics, including any content that causes “discomfort.”

Among the censored images, the state-run newspaper Global Times said last year, was the children’s cartoon Peppa Pig, which it said had become associated with “unruly slackers roaming around and the antithesis of the young generation the Party tries to cultivate.” (ByteDance later rebutted that claim, and Peppa Pig lives on in TikTok streams in the U.S.)

Patriotic messages have dominated Douyin in the weeks since the Hong Kong protests began: People’s Daily, the party’s official media outlet, posted a video last week of Hong Kong police taking a break after work, which received 1.1 million “likes” and about 40,000 comments.

TikTok’s owners have also routinely bent to government demands and intervention. ByteDance last year was forced to dismantle its popular comedy app Neihan Duanzi (roughly translated, “implied jokes”) following a government purge, during which Chinese regulators said the app’s “vulgar and improper content” had violated social morals and “caused strong disgust.”

ByteDance founder Zhang Yiming, one of China’s richest men, issued a public, self-effacing apology for content he called “in deviation of socialist core values” and pledged the company would work to ensure party “voices are broadcast to strength.”

“You cannot post anything on Douyin that contravenes the official party line on anything and expect it to remain up for long,” said Matt Schrader, a China analyst for the Washington advocacy group Alliance for Securing Democracy.

“The imprisonment of more than a million Uighurs, the corruption of upper-level party members, the videos of Hong Kong protesters: none of it stays,” he added. “Anything that’s a news source or a news app must be in line with the version of the world they want people to see."

That stance also carries into TikTok’s other major markets. The company’s head of operations in India, Raj Mishra, has said the platform would not prominently feature criticism of the country’s leaders because, as he told Bloomberg earlier this year, the app is a place “where people come to have fun rather than creating any political strife.”

TikTok today in the U.S. is an eye-catching playground of memes, music and other distractions, with thin connections to mainstream politics and no guarantee of future growth. But app experts believe it could grow into a formidable part of Americans’ online information food chain — much in the same way that Facebook, founded as an app for college students, transformed the arenas of news, politics and misinformation.

“It’s a massively untapped platform that organizations can use to change the perceptions of a massive audience,” said Rohan Midha, the managing director of PMYB, a U.K.-based marketing firm that helps coordinate corporate sponsorship deals with TikTok’s growing corps of influencers. “And most of the users are quite young, so you can reach a young demographic who it might be easier to shape their perceptions outright.”

Timothy McLaughlin in Hong Kong, Yuan Wang in Beijing and Craig Timberg in Washington contributed to this report.

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