Biggest national security concern to the US isn't Tiktok, but Apple.
21% of US people use TikTok (in 2021).
https://gs.statcounter.com/os-market-share/mobile/united-sta...
iOS is close to 60% of the mobile operating system market share in the US.
https://www.statista.com/topics/2711/us-smartphone-market/#t...
And about 50% of smartphones are Apple phones, for a bit over 40% of the US population using an iPhone.