The most recent example was Grindr which was first sold to Chinese company and the government had to force them to sell it back because the app contained location info of potentially sensitive military personnel.

Didn't they ban the use of Huawei in all telecommunication infrastructure a few months ago?

Better argument for it than for Canadian aluminum.

How come? Clearly the app is used by the youth. Having gullible youth using the app of a country that's knows for its in-app propaganda is very clearly a national security risk.

> What are the national security concerns for these apps that are not present in the multitude of other apps such as WhatsApp, Facebook Messenger, Skype, Zoom, Instagram, Twitter, Facebook, Google, Gmail, iMessage, Facetime, Vine, Snapchat, YouTube, etc?

These are all American companies. Wechat and TikTok are controlled by Chinese companies.

> What about the suspicions that Trump is upset that TikTok users helped sabotage one of his big rallies and this is retaliation and thus an overextension of his powers and an exercise in authoritarianism (something he's already done many times anyway)?

I suspect that was actually his motive, and the national security reasoning is just a pretext. That said, a stopped clock is right twice a day.