On the face of it, TikTok makes for an unlikely threat to national security.
With its snackable, seconds-long videos of viral dances and comical voice-overs, it is one of the most used apps in the west, and embedded in the culture of a generation of young people. It now claims more than 1bn users worldwide and is estimated to generate more than $10bn in revenue.
Yet the app and its Chinese owner, ByteDance, are again at the centre of a gathering geopolitical storm as governments in North America and Europe launch fresh restrictions and consider outright prohibitions on its use over fears it could be used to gather data on behalf of the Chinese state.