The Supreme Court on Friday grappled over a law that could determine the fate of TikTok, an enormously popular social media platform that has about 170 million users.

Congress enacted the law out of concern that the app, whose owner is based in China, is susceptible to the influence of the Chinese government and posed a national risk. The measure would effectively ban TikTok from operating in the United States unless its owner, ByteDance, sells it by Jan. 19.

Here are some key takeaways:

The court appeared likely to uphold the law.

While the justices across the ideological spectrum asked tough questions of both sides, the overall tone and thrust appeared to suggest greater skepticism toward the arguments by lawyers for TikTok and its users that the First Amendment barred Congress from enacting the law.

The questioning opened with two conservative members of the court, Justice Clarence Thomas and Chief Justice John G. Roberts Jr., suggesting that it was not TikTok, an American company, but its Chinese parent company, ByteDance, that was directly affected by the law.

Another conservative, Justice Brett M. Kavanaugh, focused on the risk that the Chinese government could use information TikTok is gathering on tens of millions of American teenagers and twentysomethings to eventually “develop spies, turn people, blackmail people” when they grow older and go to work for national security agencies or the military.

Justice Elena Kagan, a liberal, asked why TikTok could not just create or buy another algorithm rather than using ByteDance’s.

And another liberal, Justice Ketanji Brown Jackson, said she believed the law was less about speech than about association. She suggested that barring TikTok from associating with a Chinese company was akin to barring Americans from associating with foreign terrorist groups for national security reasons. (The Supreme Court has upheld that as constitutional.)

Still, several justices were skeptical about a major part of the government’s justification for the law: the risk that China might “covertly” make TikTok manipulate the content shown to Americans or collect user data to achieve its geopolitical aims.

Both Justice Kagan and Justice Neil M. Gorsuch, a conservative, stressed that everybody now knows that China is behind TikTok. They appeared interested in whether the government’s interest in preventing “covert” leveraging of the platform by a foreign adversary could be achieved in a less heavy-handed manner, like appending a label warning users of that risk.

Lawyers for TikTok and for its users argued that the law is unconstitutional.

Two lawyers argued that the law violates the First Amendment: Noel Francisco, representing both TikTok and ByteDance, and Jeffrey Fisher, representing TikTok users. Both suggested that concerns about potential manipulation by the Chinese government of the information American users see on the platform were insufficient to justify the law.

Mr. Francisco contended that the government in a free country “has no valid interest in preventing foreign propaganda” and cannot constitutionally try to keep Americans from being “persuaded by Chinese misinformation.” That is targeting the content of speech, which the First Amendment does not permit, he said.

Mr. Fisher asserted that fears that China might use its control over the platform to promote posts sowing doubts about democracy or pushing pro-China and anti-American views were a weaker justification for interfering in free speech than concerns about foreign terrorism.

“The government just doesn’t get to say ‘national security’ and the case is over,” Mr. Fisher said, adding, “It’s not enough to say ‘national security’ — you have to say ‘what is the real harm?’”

The Biden administration defended Congress’s right to enact the law.

The solicitor general, Elizabeth B. Prelogar, argued that Congress had lawful authority to enact the statute and that it did not violate the First Amendment. She said it was important to recognize that the law leaves speech on TikTok unrestricted once the platform is freed from foreign control.

“All of the same speech that’s happening on TikTok could happen post-divestiture,” she said. “The act doesn’t regulate that at all. So it’s not saying you can’t have pro-China speech, you can’t have anti-American speech. It’s not regulating the algorithm.”

She added: “TikTok, if it were able to do so, could use precisely the same algorithm to display the same content by the same users. All the act is doing is trying to surgically remove the ability of a foreign adversary nation to get our data and to be able to exercise control over the platform.”

The court appears unlikely to wait for Trump.

President-elect Donald J. Trump has asked the Supreme Court to issue an injunction delaying the law from taking effect until after he assumes office on Jan. 20.

Mr. Trump once shared the view that Chinese control of TikTok was an intolerable national security risk, but reversed course around the time he met with a billionaire Republican donor with a stake in its parent company.

If the court does uphold the law, TikTok would effectively be banned in the United States on Jan. 19, Mr. Francisco said. He reiterated a request that the court temporarily pause the law from taking effect to push back that deadline, saying it would “simply buy everybody a little breathing space.” It might be a “different world” for TikTok after Jan. 20, he added.

But there was scant focus by the justices on that idea, suggesting that they did not take it seriously. Mr. Trump’s brief requesting that the court punt the issue past the end of President Biden’s term so he could handle it — signed by his pick to be the next solicitor general, D. John Sauer — was long on rhetoric extolling Mr. Trump, but short on substance.

Scott Bessent, the billionaire hedge fund manager whom President-elect Donald J. Trump picked to be his Treasury secretary, plans to divest from dozens of funds, trusts and investments in preparation to become the nation’s top economic policymaker.

Those plans were released on Saturday along with the publication of an ethics agreement and financial disclosures that Mr. Bessent submitted ahead of his Senate confirmation hearing next Thursday.

The documents show the extent of the wealth of Mr. Bessent, whose assets and investments appear to be worth in excess of $700 million. Mr. Bessent was formerly the top investor for the billionaire liberal philanthropist George Soros and has been a major Republican donor and adviser to Mr. Trump.

If confirmed as Treasury secretary, Mr. Bessent, 62, will steer Mr. Trump’s economic agenda of cutting taxes, rolling back regulations and imposing tariffs as he seeks to renegotiate trade deals. He will also play a central role in the Trump administration’s expected embrace of cryptocurrencies such as Bitcoin.

Although Mr. Trump won the election by appealing to working-class voters who have been dogged by high prices, he has turned to wealthy Wall Street investors such as Mr. Bessent and Howard Lutnick, a billionaire banker whom he tapped to be commerce secretary, to lead his economic team. Linda McMahon, another billionaire, has been picked as education secretary, and Elon Musk, the world’s richest man, is leading an unofficial agency known as the Department of Government Efficiency.

In a letter to the Treasury Department’s ethics office, Mr. Bessent outlined the steps he would take to “avoid any actual or apparent conflict of interest in the event that I am confirmed for the position of secretary of the Department of Treasury.”

Mr. Bessent said he would shutter Key Square Capital Management, the investment firm that he founded, and resign from his Bessent-Freeman Family Foundation and from Rockefeller University, where he has been chairman of the investment committee.

The financial disclosure form, which provides ranges for the value of his assets, reveals that Mr. Bessent owns as much as $25 million of farmland in North Dakota, which earns an income from soybean and corn production. He also owns a property in the Bahamas that is worth as much as $25 million. Last November, Mr. Bessent put his historic pink mansion in Charleston, S.C., on the market for $22.5 million.

Mr. Bessent is selling several investments that could pose potential conflicts of interest including a Bitcoin exchange-traded fund; an account that trades the renminbi, China’s currency; and his stake in All Seasons, a conservative publisher. He also has a margin loan, or line of credit, with Goldman Sachs of more than $50 million.

As an investor, Mr. Bessent has long wagered on the rising strength of the dollar and has betted against, or “shorted,” the renminbi, according to a person familiar with Mr. Bessent’s strategy who spoke on condition of anonymity to discuss his portfolio. Mr. Bessent gained notoriety in the 1990s by betting against the British pound and earning his firm, Soros Fund Management, $1 billion. He also made a high-profile bet against the Japanese yen.

Mr. Bessent, who will be overseeing the U.S. Treasury market, holds over $100 million in Treasury bills.

Cabinet officials are required to divest certain holdings and investments to avoid the potential for conflicts of interest. Although this can be an onerous process, it has some potential tax benefits.

The tax code contains a provision that allows securities to be sold and the capital gains tax on such sales deferred if the full proceeds are used to buy Treasury securities and certain money-market funds. The tax continues to be deferred until the securities or money-market funds are sold.

Even while adhering to the ethics guidelines, questions about conflicts of interest can still emerge.

Mr. Trump’s Treasury secretary during his first term, Steven Mnuchin, divested from his Hollywood film production company after joining the administration. However, as he was negotiating a trade deal in 2018 with China — an important market for the U.S. film industry — ethics watchdogs raised questions about whether Mr. Mnuchin had conflicts because he had sold his interest in the company to his wife.

Mr. Bessent was chosen for the Treasury after an internal tussle among Mr. Trump’s aides over the job. Mr. Lutnick, Mr. Trump’s transition team co-chair and the chief executive of Cantor Fitzgerald, made a late pitch to secure the Treasury secretary role for himself before Mr. Trump picked him to be Commerce secretary.

During that fight, which spilled into view, critics of Mr. Bessent circulated documents disparaging his performance as a hedge fund manager.

Mr. Bessent’s most recent hedge fund, Key Square Capital, launched to much fanfare in 2016, garnering $4.5 billion in investor money, including $2 billion from Mr. Soros, but manages much less now. A fund he ran in the early 2000s had a similarly unremarkable performance.