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It was about an hour and a half into a hearing with the Senate Intelligence Committee when Sen. Dianne Feinstein laid into Facebook, Google and Twitter.

"I don't think you get it," she began. "You bear this responsibility. You've created these platforms, and now they are being misused. And you have to be the ones to do something about it. Or we will."

The tech giants were being grilled by Congress over Russian trolls abusing their services to meddle in last year's US election, and the California Democratic lawmaker had had it.

It was just one of very public tongue-lashings the Silicon Valley companies received over the course of three high-tension congressional panels last month, held over a two-day span. In some ways, the hearings were anticlimactic. The three companies only sent their general counsels instead of their famous CEOs -- a point several lawmakers bemoaned during the public questioning.

But in another way, it was a spotlight that symbolized a turning point for Silicon Valley: For a long time, the tech industry has enjoyed a rosy relationship with the government and the public, but now, the honeymoon's over.

For decades, Silicon Valley -- the state of mind, not merely the region 40 miles south of San Francisco -- was seen as the fertile crescent of the future. It's a place where entrepreneurs saw themselves as strivers who embody the American spirit and the ingenuity that feeds it.

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The tech industry says it's altruistic. Google is organizing the world's information, Facebook is connecting the world and bringing it closer together. And because the companies created jobs, wealth and services that genuinely make life easier, they also had a cozy rapport with policymakers. Their lobbying arms focused on benign stuff like tax reform and professional visas.

Then the presidential election happened -- the bitter, exhausting, Russian-meddled tweet-fest that engulfed the country as shocker after shocker led to the upset election of Donald Trump. The more than year-long campaign season, which even Trump described on his election night as sowing "wounds of division," exposed many things about Silicon Valley that Congress, and much of the country, did not like.

The tech giants have faced controversy before, but this time is different. Until now, no transgression reached the caliber or seriousness of the Russian meddling scandal. One reason lawmakers are being so aggressive is that they feel threatened, says Chris Hoofnagle, a professor at the UC Berkeley School of Information. Modern elections are played out on social media, and Facebook, Google and Twitter have all the power.

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"Both Democrats and Republicans are afraid," says Hoofnagle. "This is the new playing field, and they can't control it."

In the doghouse

After decades of goodwill, now it seems like the tech giants can't do anything right. Aside from the election controversy, Google, Twitter and Facebook have faced other pitfalls: Violent content. Online bullying. Algorithms gone haywire.

Google has been especially egregious at spreading fake news during national tragedies -- after both the Las Vegas and Texas shootings, the search engine promoted misinformation about the shooters. The company's woes go beyond its search engine, too. YouTube, owned by Google, has been under fire for letting disturbing videos aimed at kids past its filters.

Twitter has been a cesspool of bullying and a haven for white supremacists. Jack Dorsey, the company's chief executive, is playing a years-in-the-making game of whack-a-mole, overhauling the social network's abuse policies to make the environment less toxic. Last month, he suspended Twitter's verification program, which issues coveted blue check marks to notable Twitter accounts, partly because the badge gave too much of a spotlight to white supremacists.

Facebook Live, the social network's live video-streaming service, has broadcast killings, rape and other violence unchecked over the internet. Meanwhile, Mark Zuckerberg, Facebook's founder, took a tone-deaf virtual reality tour though hurricane-ravaged Puerto Rico, and was swiftly called out for his cluelessness.

And that's not a complete list of their missteps.

"What Google and Facebook did, one of the ways they sold their products, was with emotion," Hoofnagle says. He cites their lofty mission statements, like Zuckerberg's "messianic" proclamation to connect the world. So when things go awry, the severe blowback is a consequence of leaning so hard into that emotional pitch. "Instead of just, 'I dislike Facebook,' it's 'I hate Facebook.'"

An unfamiliar position

For much of this year, the tech giants have been on the defensive. Zuckerberg, after infamously saying last year that the notion of fake news affecting the election was "pretty crazy," began this year by posting a nearly 6,000-word manifesto on Facebook's new role in the world. He coupled that with a nationwide tour he said was meant to discover how Americans outside his San Francisco bubble live. It was slickly photographed and documented every step of the way. The trip even had its own logo.

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Google has sought to make nice with steel towns and the heartland as well. In October, CEO Sundar Pichai traveled to Pittsburgh to introduce a new program called "Grow with Google," aimed at training people for the "changing nature of work." It's a change that Google and the other tech giants had a major hand in making with their software and automated technology. Part of the program includes Google hosting sessions in which its staffers travel across the country, teaching people how to use Google's employment tools. The tour kicked off last month in Indianapolis. In all, Google pledged $1 billion to work-related initiatives around the world.

As Silicon Valley companies have grown to become the most powerful corporations in the world, their actions have had unintended consequences. In the Valley, the idea of "disruption" is celebrated. It stands for that relentless, scrappy drive to remake industries to be, in the eyes of entrepreneurs, faster, smarter, more efficient.

"That notion of disruption sounds interesting," says Bob O'Donnell, an analyst with Technalysis Research. "But when it comes to people's day-to-day lives, that's not necessarily what they want," if it means lost jobs or reading misinformation.

And that's something the tech giants will have to take to heart from here on out.

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