The opinion seems to be that there is no authority with the president/executive to promulgate such a ban, so I doubt it is within constitutional limits to do so

The opinion seems to be that there is no authority with the president/executive to promulgate such a ban, so I doubt it is within constitutional limits to do so. However, there is some limited commercial/trade related measures available, but these are rather new and untested, and will likely expose the federal government to litigation. The question is about how can something that isn't illegal or that hasn't evidently broken laws be banned, and that too without even a semblance of a fair process. Was TikTok investigated, if so what was found? Have they been asked to show cause? Have they broken laws? See: https://foreignpolicy.com/2020/07/24/trump-cant-ban-tiktok-free-chinese-apps/ https://foreignpolicy.com/2020/07/24/trump-cant-ban-tiktok-f...