In the summertime of 2020, in full re-election mode and on the lookout for new methods to punish China, President Donald J. Trump threatened to chop off TikTok from the telephones of thousands and thousands of People except its mum or dad firm agreed to promote all of its U.S. operations to American homeowners. The hassle collapsed.

Now, greater than two years later, after prolonged research of how Chinese language authorities may use the app for all the things from surveillance to info operations, the Biden administration is making an attempt a strikingly comparable transfer. It’s higher organized, vetted by legal professionals, and coordinated with new payments in Congress that seem to have appreciable bipartisan help.

But making TikTok protected from Chinese language exploitation — as a instrument for Chinese language officers to surveil People’ tastes and whereabouts, as an entry level into the telephones that comprise their complete lives and as a technique to pump out disinformation — seems to be more durable than it appears.

The tensions over the app will come to a head on Thursday, when TikTok’s Singapore-based chief govt, Shou Chew, testifies earlier than the Home Power and Commerce Committee, a listening to that can give Democrats and Republicans alike a uncommon likelihood to air their suspicions on to the corporate. On Tuesday, Mr. Chew posted a TikTok from the corporate’s essential account, declaring that “some politicians” try to take the app away from 150 million customers in the USA, together with small companies.

However after two years of negotiations with TikTok about constructing in new protections, it’s not clear there’s something the corporate can do, in need of turning all the operation over to People, that can fulfill the issues of U.S. intelligence businesses. The Justice Division’s No. 2 official and others have successfully rejected proposals by TikTok’s company mum or dad, ByteDance, to handle the issues.

Any choice to take away the app, both banning it for 150 million customers in the USA or blocking additional downloads, could be politically fraught for Mr. Biden. Nobody encapsulated the political dilemma extra pithily than Gina Raimondo, the commerce secretary, who’s on the middle of latest export controls imposed on high-technology items to China.

“The politician in me thinks you’re going to actually lose each voter beneath 35, ceaselessly,” she stated lately to Bloomberg Information.

Ms. Raimondo and different officers shortly add that dangerous politics isn’t any motive to again away from a complete ban if the nationwide safety risk warrants it. The issue is made extra complicated by the truth that among the world’s largest information organizations, together with The New York Instances, now have TikTok accounts, that means that shutting down the app may look like shutting down the unfold of fact-based information to counter Chinese language disinformation.

“Numerous this can be a recreation of rooster,” stated James A. Lewis, who runs the cyberthreats program on the Middle for Strategic and Worldwide Research. However he believes Mr. Biden has a far higher likelihood of success than his predecessor did.

“Totally different from the Trump administration, I believe this administration has an opportunity of profitable — attitudes have modified towards China,” he stated. A number of new payments that might, in numerous methods, give express new authority to the president to close down TikTok have acquired bipartisan help. They’re propelled by the intelligence neighborhood’s conclusion, contained within the Worldwide Menace Evaluation delivered to Congress, that China stays the “broadest, most lively and chronic” cyberthreat to the nation.

But to this point, the risk from TikTok is basically theoretical.

There have been a handful of circumstances of abuse, together with efforts to geolocate reporters who revealed leaked details about the corporate. However the administration has not offered complete, declassified proof of a systemic effort to make use of the app to advance the Chinese language authorities’s assortment efforts.

That has not stopped almost 30 states from banning TikTok from official authorities or contractor telephones, and federal workers are being made to take away it as nicely — although not from their private gadgets.

There are three areas of clear concern. The primary is the place TikTok shops the information of its United States customers. Till lately, a lot of it was on ByteDance-run servers in Singapore and Virginia, which many feared would permit China to require TikTok to show over consumer information beneath Beijing’s nationwide safety legal guidelines. This 12 months TikTok tried to pre-empt this argument, saying it might delete the information of its American customers from the ByteDance servers and transfer them to servers run by Oracle, an American cloud computing agency.

Then comes the more durable query — who writes the algorithm, the code that’s TikTok’s secret sauce. That code assesses a consumer’s decisions and makes use of them to pick extra materials to feed the consumer — a favourite dance routine, or possibly an attention-grabbing information story. The algorithms have been written in China, by Chinese language engineers who’ve refined the artwork of giving customers what they need to see. The concern, Matt Perault and Samm Sacks wrote lately on the Lawfare weblog, is that “TikTok may unilaterally determine to prioritize content material that might threaten or destabilize the USA.” Once more, it hasn’t occurred but, at the very least not via TikTok.

And eventually, there’s the problem of whether or not an app whose algorithm few perceive could possibly be a gateway for outsiders, together with the Chinese language ministry of state safety, to get into the telephones of People — to seek out out not their dance preferences, however the huge trove of information they carry round of their hip pockets.

In November, Christopher A. Wray, the F.B.I.’s director, warned that the Chinese language authorities may use TikTok’s algorithm for “affect operations.” Gen. Paul M. Nakasone, the top of U.S. Cyber Command and the director of the Nationwide Safety Company, echoed these issues this month, saying that “it’s not solely the truth that you’ll be able to affect one thing, however you can even flip off the message as nicely when you may have such a big inhabitants of listeners.”

TikTok has sought to reply to misinformation issues with a prolonged checklist of up to date insurance policies for moderating movies, together with new restrictions and labeling guidelines for deepfakes — extremely lifelike pretend movies made with synthetic intelligence. TikTok, for instance, won’t permit deepfakes of personal figures and can bar these of public figures if the content material is used for endorsements. It additionally provided extra element on the way it will “defend civic and election integrity.”

A spokeswoman for TikTok didn’t reply to a request for remark.

The battle over the app had already develop into a knotty authorized problem by the point Mr. Biden inherited it from Mr. Trump in 2021.

Federal courts had dominated that Mr. Trump didn’t have the ability to execute his proposed ban of the app from Apple’s and Google’s app shops, taking away essential leverage the White Home had used to get ByteDance to think about promoting TikTok.

Mr. Biden issued an govt order in June 2021 rolling again Mr. Trump’s risk of a ban. He left in place the order that demanded ByteDance divest the app. However workers members for a gaggle of federal businesses that vet overseas corporations in America, the Committee on Overseas Funding in the USA, had been contemplating a 3rd choice: negotiating an settlement with TikTok that might resolve the nationwide safety issues however cease in need of forcing ByteDance to promote the app.

Underneath its newest proposal, TikTok wouldn’t solely retailer U.S. consumer information on Oracle servers in the USA; the cloud computing firm would additionally monitor its content material suggestion algorithm — which TikTok says is a hedge towards the app getting used to unfold propaganda. And the entity governing the app in the USA could be overseen by a board of three folks accredited by the federal government.

However that proposal didn’t fulfill hawks in Washington. Some within the administration — together with Lisa O. Monaco, the deputy lawyer common — had issues its phrases weren’t strict sufficient. The administration additionally confronted rising strain from lawmakers who stated the app needs to be banned fully.

Now, the Biden administration is pursuing a brand new technique.

Publicly, it backed laws earlier this month from a bipartisan group of senators that might give the Commerce Division clearer energy to ban the app, doubtlessly restoring the federal government’s leverage over ByteDance. Privately, administration officers instructed TikTok they wished its Chinese language possession to promote the app or face a potential ban. Ought to the laws cross, it might considerably strengthen the administration’s hand in forcing a sale.

Peter Harrell, a lawyer and former senior director for worldwide economics and competitiveness on the Nationwide Safety Council, stated the proposed laws is “essential as a result of because the U.S. offers with TikTok and different Chinese language apps it wants some clear-cut authorized authorities to control and compel actions” that don’t exist in present regulation.

A White Home spokeswoman declined to remark past pointing to its present help for the laws.

At moments, TikTok has undercut its personal arguments. It has stated it might not flip over details about its customers to the Chinese language authorities — although China’s nationwide safety regulation would clearly require it to just do that if the nation’s intelligence companies ordered its Chinese language workers to take action.

When Forbes reported in October {that a} China-based group at ByteDance deliberate to make use of TikTok to watch the places of some People, TikTok’s communications group responded on Twitter that the publication’s work lacked “each rigor and journalistic integrity.” It additionally stated TikTok had “by no means been used to ‘goal’” U.S. politicians or journalists.

Two months later, ByteDance admitted that 4 of its workers, together with two based mostly in China, had gained entry to the IP addresses and different information of two reporters, in addition to some folks related to the reporters via their TikTok accounts. The staff had been attempting to find out if the people had been assembly with ByteDance workers, so they may try and discern the supply of leaks to the journalists.

TikTok dismissed the case as an anomaly, and fired the workers. It stated it arrange methods to stop a recurrence. And with out query, American corporations have had comparable insider incidents of privateness breaches.

However within the present ambiance in Washington, particularly after the downing of a Chinese language surveillance balloon that crossed the USA in January, any proof of Chinese language surveillance feeds a deep, bipartisan want to crack down on China’s entry factors to American networks. And of these, there isn’t a greater one — or extra influential — than TikTok, which is why the trail the administration takes over the subsequent few months could set a precedent that goes far past TikTok’s rapid destiny.

Julian Barnes contributed reporting from Washington.