TikToks future prospects in the United States looked grimmer than ever Friday, following a bruising day of Supreme Court arguments in a case that could determine whether the app is forced to shut down on January 19.A lawyer for TikTok spent hours arguing that the law Congress passed last yearwhich requires TikToks Chinese parent company ByteDance to sell the app or face a ban in the U.S.infringes on TikToks free speech rights. Congress passed the law, argued lawyer Noel Francisco, out of fear that Americans, even if fully informed, could be persuaded by Chinese misinformation. But that possibility, he said, is something that the First Amendment leaves to the people.But TikToks argument seemed to fall on unsympathetic ears, as both conservative and liberal justices pushed back, stating that the law targets TikToks ownership, not the speech it publishes. TikTok is going to suffer some pretty severe incidental effects, but they are incidental, said liberal justice Elena Kagan during questioning. The law is only targeted at this foreign corporation [ByteDance], which doesnt have First Amendment rights.The court appeared far more open to the governments argument that TikToks Chinese ties pose a substantial national security riskone that they seem to believe the government has the legal authority to mitigate. There is a long tradition of preventing foreign ownership or control of media in the United States, said conservative justice Brett Kavanaugh. That history has to be important.At issue in this case is the Protecting Americans from Foreign Adversary Controlled Applications Act, which President Biden signed into law last year. The law would prevent app stores and internet hosting services from providing services to ByteDance, TikTok, and any of its affiliates by categorizing them as foreign adversary controlled applications. Cutting off access to app stores and hosting platforms would require the app to go dark, Francisco said Friday.The government has argued that this so-called divest-or-ban law is necessary to mitigate the risks that TikToks ties to China pose, claiming that connection makes the app vulnerable to manipulation and propaganda, as well as data weaponization. The law also creates a mechanism for the president to identify other foreign adversary controlled applications that might pose a national security threat. The only way for these applications to avoid being cut off is for the foreign entities that control them (in this case, ByteDance) to divest.The Act has been roundly condemned, not just by TikTok, but by a wide range of First Amendment scholars and advocates, who say that allowing the government to shutter a massive platform of free speech, using only a vague national security justification as pretext, would set a dangerous precedent. The government, for its part, has maintained that the law sidesteps the First Amendment by enabling TikTok to continue operating, provided its ownership changes hands in a way that satisfies national security concerns. (Indeed, Shark Tanks Kevin OLeary and Los Angeles Dodgers owner Frank McCourt have emerged as leading bidders to purchase the U.S. version of the app.)In December, a D.C. circuit court upheld the law, giving weight to the governments assessment of TikToks risks and agreeing that the law is not an explicit crackdown on content. What the act targets is the [Peoples Republic of Chinas] ability to manipulate that content covertly, one of the judges in that case wrote. Understood in that way, the governments justification is wholly consistent with the First Amendment.On Friday, many of the Supreme Court justices appeared to agree. Youre wrong about the statute being read as saying: TikTok, you have to go mute, said liberal justice Ketanji Brown Jackson. TikTok can continue to operate on its own algorithm, on its own terms, as long as its not associated with ByteDance.The law doesnt say TikTok has to shut down, said conservative justice Amy Coney Barrett. If ByteDance was willing to let you go and willing to let you take the source code with you, that would be fine. We would not be here.Francisco repeatedly argued that Congress had failed to pursue less restrictive means of addressing the risks raised by the law. They could, for example, require that TikTok more clearly disclose its Chinese ties to users, a proposal that the justices also appeared to find lacking. Thats the only remedy the government could undertake? liberal justice Sonia Sotomayor asked dubiously.Francisco also pointed to the fact that the law leaves out a whole range of Chinese-owned firms, including e-commerce giants like Shein and Temu, which collect massive amounts of data themselves. This, he suggested, is evidence that the governments primary concern is with the potential for speech on TikTok to be manipulated. [The law] says theres one speaker were particularly concerned about, and were going to hammer home on that one speaker, he said. The reason theyre targeting that speaker is because theyre worried about the future content on that platform.While the court appeared more amenable to the governments arguments, Solicitor General Elizabeth Prelogar hardly skated through arguments. Prelogar leaned heavily on the idea that the Chinese government could use TikTok to send covert messages to Americans that pit them against one another or otherwise advance Chinese interests, without users being privy to the fact that a foreign government is pulling the strings.Isnt that a pretty paternalistic point of view? asked conservative justice Neil Gorsuch. Dont we normally assume that the best remedy for problematic speech is counter speech? Still, even these pointed exchanges seemed far outweighed by the courts doubts about TikToks arguments.The court is now in a race against a ticking clock. The law requires the divestment to be at least set in motion by January 19 in order to avoid a ban. Incoming president Donald Trump, who is set to be inaugurated a day later, has signaled his interest in stopping the ban, but the law only gives him the option of temporarily postponing it from going into effect if a divestment deal is underway. So far, all signs suggest ByteDance is unwilling to move.But in her remarks, Prelogar said the government always anticipated the company would play a game of chicken. If the court upholds the ban, she said, it might be just the jolt that Congress expected the company would need to actually move forward.