NYT

TikTok has long presented a parenting problem, as millions of Americans raising preteens and teenagers distracted by its viral videos can attest. But when the C.I.A. was asked recently to assess whether it was also a national security problem, the answer that came back was highly equivocal.

Yes, the agency’s analysts told the White House, it is possible that the Chinese intelligence authorities could intercept data or use the app to bore into smartphones. But there is no evidence they have done so, despite the calls from President Trump and Secretary of State Mike Pompeo to neutralize a threat from the app’s presence on millions of American devices.

It made little difference. When Mr. Trump issued an executive order on Thursday that would effectively ban TikTok from operating in the United States in 45 days — part of an effort to force a sale of the app to an American company, most likely Microsoft — he declared it threatened “the national security, foreign policy and economy of the United States.”

In a surprise addition, he issued a similar ban on WeChat, a Chinese social media app on which millions of people, largely outside the United States, conduct everyday conversations and financial transactions.

There is no doubt the actions by the administration are the toughest since it took steps last year to block the use of Huawei telecommunications equipment by American companies. And there is a fear running through Silicon Valley that Mr. Trump — seen as eager to punish the Chinese, and as angry at viral TikTok videos that mock him and at the app’s role in deterring attendance at his rally in June in Tulsa — is opening the door for countries around the world to declare Facebook and Google to be similar threats to their own security.

Measuring national security threats has always been tinged as much by politics as intelligence assessments: Think of John F. Kennedy’s warning of the “missile gap” with the Soviets in the 1960 election, or George W. Bush’s declaration of an imminent Iraqi nuclear ability on his ill-fated march to war 17 years ago.

Mr. Trump’s warning about the Chinese threat has been expanding: Days before the executive order, the State Department announced a “Clean Network” initiative, threatening to ban not only apps, but Chinese undersea cables, telecommunications firms that have operated in the United States for years and businesses that store information in the cloud.

Sorting out the real threats from the imagined ones is as complex as the design of the internet. But the threat TikTok poses, intelligence officials say, pales to the one created by Huawei, the Chinese telecommunications giant that was seeking to wire up the United States, Europe and much of the developing world, using the transition to 5G networks to control global communications.

“Is TikTok a problem?” Senator Mark Warner, Democrat of Virginia and the ranking member of the Senate Intelligence Committee, said on Thursday at the Aspen Security Forum.