What is America to do about TikTok? Its quirky videos have attracted 150mn active US users. Yet US officials fear Beijing could subvert the Chinese-owned app to spy on Americans or spread propaganda. Many parents, meanwhile, worry about TikTok’s impact on teenage mental health. Talks with a US watchdog over the app’s plans to ringfence US data on American servers have foundered. CEO Shou Zi Chew’s recent appearance before lawmakers failed to assuage their concerns. The Biden Administration has issued an ultimatum to TikTok’s Chinese owners: sell the US unit — which Beijing has said it would oppose — or face a potential ban. But a ban would infuriate legions of young Americans.

The national security case against TikTok is that companies with a presence in China are obliged to hand over data if asked to assist state intelligence. TikTok’s Chinese parent ByteDance is 60 per cent owned by global investors; employees have 20 per cent. But its Chinese founder Zhang Yiming owns the rest and has control through supervoting shares, people close to ByteDance say.

Chew insists TikTok has never been asked to submit US data to Chinese officials, and never would. No evidence of mass surveillance has been presented. But cases have emerged in the past year of China-based ByteDance employees accessing American user data, including that of journalists. Security officials warn, too, that TikTok’s potent algorithm could be tweaked to sow misinformation on behalf of Beijing.