TikTok Free Speech Rights Offer a Bulwark Against a Forced Sale

If Congress forces ByteDance Ltd. to sell TikTok Inc. or face a US ban, the social media company is expected to reprise First Amendment arguments that have so far successfully kept the app from being blocked in Montana.

A potential lawsuit seeking to block the forced divestiture legislation on those grounds would set up a legal showdown between free-speech concerns and the federal government’s ability to restrict a foreign-owned social media platform used by more than 150 million Americans.

TikTok is equipped with a strong arsenal of legal arguments, attorneys say, namely that the company has a right to operate ...