Tech is once again in Washington's spotlight, and not in a good way.

Facebook COO Sheryl Sandberg, Twitter CEO Jack Dorsey and Larry Page, CEO of Google's parent company Alphabet, have been invited to testify before committees on Capitol Hill Wednesday.

But they're not there to spread the gospel of free speech, the open internet or the wonders of technology. The Senate Select Committee on Intelligence wants to talk about "Foreign influence operations and their use of social media platforms." The House of Representatives Energy and Commerce Committee, meanwhile, has titled its hearing "Twitter: Transparency and Accountability."

"When decisions about data and content are made using opaque processes, the American people are right to raise concerns," House Energy and Commerce Chairman Greg Walden said in a statement. "This committee intends to ask tough questions."

It's hard to remember that Silicon Valley was once the darling of American industry, viewed by many as the country's innovative heartland.

Four years ago, 76 percent of internet users Pew surveyed considered the online social climate to be "mostly kind," even though harassment was actually a nonstop occurrence. Survey after survey glowed about tech and its impact on the world. Even up to just a year ago, people were wondering whether Facebook CEO Mark Zuckerberg would one day run for elected office -- even president.

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The honeymoon is decidedly over. The tech industry is mired in an endless string of scandals about Russian election interference, data privacy and censorship. More than half of Americans said earlier this year that the government should regulate tech companies, according to market research firm HarrisX. And all those people who felt the internet was "mostly kind" four years ago? Pew now says nearly two-thirds of US adults believe harassment is "a major problem," and most of them believe it's the tech industry's job to fix it.

Which is why policy and government experts say Facebook, Twitter and Google's upcoming testimony is just the beginning of a backlash against the tech industry.

"You're starting to see people say, 'Wait a minute, who are these companies and what are they doing? And what the hell have we been allowing them to do?'" said Paul Argenti, a professor of corporate communications at Dartmouth College's Tuck School of Business. "The bubble has burst, the saber swords are out."

Facebook, Twitter and Google each declined to make executives available for interviews before Wednesday's testimonies.

More questions, more fixes

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Zuckerberg talked about data privacy when he sat before three congressional committees over two days in April. Facebook had just admitted that up to 87 million people's account information had been leaked to Cambridge Analytica without their permission. While there, lawmakers pushed him about how Facebook could have let Russian election interference happen despite the obvious clues (among other things, political ads were being paid for in Russian rubles).

In the nearly half year since his testimony, the tech industry has attempted a number of reforms. Facebook, for example, has cut off access to people who abuse its data. It's also banned hundreds of accounts suspected of using its service to interfere in elections worldwide and spread false news. Both Facebook and Twitter now have websites showing the political ads that have run on their platforms, including how much was spent and how many people they reached.

"It shows that they're listening; they've committed resources and they recognize there's a problem," said James Norton, who had been a deputy assistant for the Department of Homeland Security in the George W. Bush administration.

The question now, he said, is whether their efforts will be enough to satisfy Congress. If so, the companies will likely be asked to return after the midterm elections. But if Wednesday's hearings go poorly, the companies could be summoned to testify even earlier.

"We, I think, have only begun to do our oversight," Rep. Adam Schiff, a Democrat from California, said in an April interview.

That's assuming members of Congress understand the nuances of what they're hearing. Zuckerberg's testimony on Capitol Hill exposed how poorly some lawmakers understand technology or the industry behind it.

"If [a version of Facebook will always be free], how do you sustain a business model in which users don't pay for your service?" Sen. Orrin Hatch, the 84-year-old Republican from Utah, asked early in the Senate's five-hour hearing.

Zuckerberg paused a moment as if stunned by the question, then answered, "Senator, we run ads." The staff sitting behind him grinned at the response.

Later, Sen. Brian Schatz asked if Facebook would be able see what he "emailed" someone over WhatsApp. "Senator no," Zuckerberg replied. "WhatsApp is encrypted. We can't see any of that."

That's why Schiff, who's both a member of the House Permanent Select Committee on Intelligence and a rumored contender to become the next Speaker of the House, said he expects fellow lawmakers will do their homework. "Silicon Valley and social media are not the only complicated issues that we deal with here."

The question now will be whether these hearings will mark a turnaround of public perception, or a tipping point when things got worse.

Both the Senate and House hearings will be carried live on television and streamed over the web. The Senate hearing begins at 9:30 a.m. ET/6:30 a.m. PT and can be watched here. The House hearing will begin at 1:30 p.m. ET/10:30 a.m. PT and can be watched here.

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