In the Apple Case, a Debate Over Data Hits Home

"It's healthy for our democracy," he told reporters at the time. "I think it's a sign of maturity."

But the national debate touched off this winter by the confrontation between the Justice Department and Apple over smartphone security is not exactly the one Mr. Obama had in mind.

Mr. Snowden's revelations produced modest changes and a heightened suspicion of the government's activities in cyberspace. Because the issue now centers on a device most Americans carry in their pockets, it is concrete and personal in a way that surveillance by the National Security Agency never was.

The trade-offs seem particularly stark because they have been framed around a simple question: Should Apple help the F.B.I. hack into an iPhone used by a gunman in the massacre last December in San Bernardino, Calif.?

Law enforcement officials have been adamant they must be able to monitor the communications of criminals. They received a vote of confidence from Mr. Obama on Friday, when he said the "absolutist" position taken by companies like Apple is wrong. But the pushback has been enormous.

In the month since a judge ordered Apple to comply with the F.B.I., the debate has jumped from the tech blogs to the front pages of daily newspapers and nightly newscasts. Supporters of the company's position have held rallies nationwide. Late-night comedians have lampooned government snoopers. Timothy D. Cook, the usually publicity-shy Apple chief executive, pleaded his case on "60 Minutes" last December. On Twitter, "#encryption" fills the screen with impassioned debate on both sides.

"Discussing the case with my friends has become a touchy subject," said Matthew Montoya, 19, a computer science major at the University of Texas, El Paso. "We're a political bunch with views from all across the spectrum."

The novelist Russell Banks, who signed a letter to Attorney General Loretta Lynch on behalf of Apple, said he had spoken with more than a dozen people about the case just in the last week.

"It's not just people in the tech industry talking about this," Mr. Banks, the author of "Affliction" and "The Sweet Hereafter," said. "It's citizens like myself."

That may be because the Apple case involves a device whose least interesting feature is the phone itself. It is a minicomputer stuffed with every detail of a person's life: photos of children, credit card purchases, texts with spouses (and nonspouses), and records of physical movements.

Mr. Obama warned Friday against "fetishizing our phones above every other value." After avoiding taking a position for months, he finally came down on the side of law enforcement, saying that using technology to prevent legal searches of smartphones was the equivalent of preventing the police from searching a house for evidence of child pornography.

"That can't be the right answer," he said at the South by Southwest festival in Texas, even as he professed deep appreciation for civil liberties and predicted both sides would find a way to cooperate. "I'm confident this is something that we can solve."

But polls suggest the public is nowhere near as certain as Mr. Obama. In surveys, Americans are deeply divided about the legal struggle between the government and one of the nation's most iconic companies. The polls show that Americans remain anxious about both the threat of terrorist attacks and the possible theft of personal digital information.

A Wall Street Journal/NBC News survey released last week found that 42 percent of Americans believed Apple should cooperate with law enforcement officials to help them gain access to the locked phone, while 47 percent said Apple should not cooperate. Asked to weigh the need to monitor terrorists against the threat of violating privacy rights, the country was almost equally split, the survey found.

That finding may have seemed unlikely in the wake of terrorist attacks last year in Paris and San Bernardino. In December, eight in 10 people said in a New York Times/CBS News survey that it was somewhat or very likely that there would be a terrorist attack in the United States in the coming months. A CNN poll the same month found that 45 percent of Americans were somewhat or very worried that they or someone in their family would become a victim of terrorism.

But despite the fears about terrorism, the public's concern about digital privacy is nearly universal. A Pew Research poll in 2014 found more than 90 percent of those surveyed felt that consumers had lost control over how their personal information was collected and used by companies.

The Apple case already seems to have garnered more public attention than the Snowden revelations about "metadata collection" and programs with code names like Prism and XKeyscore. The comedian John Oliver once mocked average Americans for failing to know whether Mr. Snowden was the WikiLeaks guy or the former N.S.A. contractor (he was the latter).

Now, people are beginning to understand that their smartphones are just the beginning. Smart televisions, Google cars, Nest thermostats and web-enabled Barbie dolls are next. The resolution of the legal fight between Apple and the government may help decide whether the information in those devices is really private, or whether the F.B.I. and the N.S.A. are entering a golden age of surveillance in which they have far more data available than they could have imagined 20 years ago.

"It's an in-your-face proposition for lots more Americans than the Snowden revelation was," said Lee Rainie, director of Internet, science and technology research at Pew Research Center.

Cindy Cohn, executive director of the Electronic Frontier Foundation, said: "Everyone gets at a really visceral level that you have a lot of really personal stuff on this device and if it gets stolen it's really bad. They know that the same forces that work at trying to get access to sensitive stuff in the cloud are also at work attacking the phones."

For the F.B.I. and local law enforcement agencies, the fight has become a high-stakes struggle to prevent what James B. Comey, the bureau's director, calls "warrant-free zones" where criminals can hide evidence out of reach of the authorities.

Officials had hoped the Apple case involving a terrorist's iPhone would rally the public behind what they see as the need to have some access to information on smartphones. But many in the administration have begun to suspect that the F.B.I. and the Justice Department may have made a major strategic error by pushing the case into the public consciousness.

Many senior officials say an open conflict between Silicon Valley and Washington is exactly what they have been trying to avoid, especially when the Pentagon and intelligence agencies are trying to woo technology companies to come back into the government's fold, and join the fight against the Islamic State. But it appears it is too late to confine the discussion to the back rooms in Washington or Silicon Valley.

The fact that Apple is a major consumer company "takes the debate out of a very narrow environment — the universe of technologists and policy wonks — into the realm of consumers where barriers like the specific language of Washington or the technology industry begins to fall away," said Malkia Cyril, the executive director of the Center for Media Justice, a grass-roots activist network.

That organization and other activist groups like Black Lives Matter have seized on the issue as important for their members. In February the civil liberties group Fight for the Future organized the day of protest against the government order that resulted in rallies in cities nationwide.

"When we heard the news and made a call for nationwide rallies, one happened in San Francisco that same day," said Tiffiniy Cheng, co-founder of Fight for the Future. "Things like that almost never happen."

Ms. Cyril says the public angst about the iPhone case feels more urgent than did the discussion about government surveillance three years ago.

"This is one of those moments that defines what's next," she said. "Will technology companies protect the privacy of their users or will they do work for the U.S. government? You can't do both."