Being removed from US App Marketplaces (Apple, Android, Microsoft, Amazon, etc), forbidden from doing business with US Advertising companies (Google, etc), forbidden from Banking in the US, and forbidden from working with US technology/hosting/cloud companies - TikTok rots and eventually becomes untenable to operate within the US.
I like to think that an open system like this would outcompete the PRC propaganda machine.
Central blocking on DNS side etc. is unlikely.
Sure, they could accept money from people in US through Bitcoin, but I don't think they business would be exactly viable if that's their payment model.
If they had no physical, legal, and financial presence in the US, then sure, it would be somewhat impossible to sue them.
However, TikTok is registered as a legal business entity in the US, they have employees in the US working for that business entity, they have physical properties (that they likely lease) where said employees work, and they have money going through their US accounts.
In the TikTok scenario specifically, it makes perfect sense to me why and how the US would sue them.
Also, I am not even sure that this applies here, as I couldnt even find anything about the US government suing TikTok. All I could find was that TikTok is the one that filed with the US courts to fight the bill that is getting them banned, i.e., they are the ones actually suing the US government[0].
0. https://www.latimes.com/entertainment-arts/business/story/20...
It's not long, to quote it omitting definitions, enforcement mechanisms, timelines, and appeals process (which are also not long and I encourage you to read if you have questions as to the details):
> (Sec. 2) This division prohibits distributing, maintaining, updating, or providing internet hosting services for a foreign adversary controlled application (e.g., TikTok). However, the prohibition does not apply to a covered application that executes a qualified divestiture as determined by the President.
> Additionally, the division requires a covered foreign adversary controlled application to provide a user with all available account data (including posts, photos, and videos) at the user's request before the prohibition takes effect. The account data must be provided in a machine-readable format.
So yeah, if tiktok makes an apk available on a non-us server it looks like you should just need to download and install it (assuming the bill goes into affect and bytedance doesn't divest/the courts don't stop it). It's not a particularly broad ban, nor does it seem like it needs to be to be effective.