“The constitutional law here appears straightforward: Congress can’t outright ban TikTok or any social media platform unless it can prove that it poses legitimate and serious privacy and national security concerns that can’t be addressed by any other means. The bar for such a justification is necessarily very high in order to protect Americans’ First Amendment rights, Krishnan said.”
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“members of Congress have not provided concrete proof for their claims about Chinese digital espionage and seem to have little interest in offering any transparency: Before the committee voted to advance the bill Thursday, lawmakers had a closed-door classified briefing on national security concerns associated with TikTok.”
https://www.vox.com/politics/24094839/tiktok-ban-bill-congress-pass-biden