Facebook chief Mark Zuckerberg appears at a hearing before the House Energy and Commerce Committee on Wednesday in Washington. (Matt McClain/The Washington Post)

Two days of sharp questioning of Facebook chief executive Mark Zuckerberg underscored how the risks posed by social media have become areas of broad political concern, bringing together House and Senate, Democrat and Republican, even rural and urban lawmakers.

The uncommonly bipartisan flavor of the hearings manifested itself in numerous threats by members of both parties to more forcefully regulate the technology industry — a development that Zuckerberg and some other tech leaders now seem to expect and accept, at least in concept.

But many longtime advocates for reining in the industry remain unconvinced that federal action is imminent after more than a decade in which privacy controversies have failed to generate meaningful new laws. Few expect a reversal this year with a looming election, a Congress riven by partisan discord and a White House weakened by federal investigation.

The unified tone of Wednesday’s hearing didn’t even survive the day. As soon as it adjourned, lawmakers began trading barbs with each other.

Some advocates of federal action on technology issues hold out hope that a more modest effort to regulate online political advertising could advance. But that could lag behind efforts by individual states and Europe, where a dramatic rewriting of privacy laws is forcing Facebook and other technology companies to adapt in ways that are already having a global impact, including for American consumers.

“The clock is ticking, and we will see pressure building for Congress to eventually act,” said Jeff Chester of the Center for Digital Democracy. Zuckerberg’s “testimony has helped the privacy issue cross a critical threshold of public understanding. Anger is building. This was the beginning — not the end — of their Internet privacy fight.”

Yet hopes that Congress will soon grapple with the deeper, systemic and complex issues of digital privacy remain unlikely to be fulfilled as Washington lurches from crisis to crisis, say longtime watchers of these issues.

“Even with this strong bipartisan consensus that there’s a large problem that needs legislative action, it would be extremely difficult to pass a law in this environment,” said Gene Kimmelman, president of Public Knowledge, a Washington-based consumer advocacy group. He predicted changes probably would take years.

Zuckerberg’s 10 hours of testimony this week, replete with apologies and promises to rectify past problems, may have temporarily quelled demands for a rapid, forceful government response to recent controversies.

Kimmelman and others said they detected a loosening of the long-standing political stagnation on technology issues, whether that’s understood as better protecting privacy, thwarting Russian disinformation or both.

Even one skeptic of forceful federal action, Rep. Billy Long (R-Mo.), chided fellow lawmakers in Wednesday’s hearing of the House Energy and Commerce Committee, saying, “Congress is good at two things: doing nothing and overreacting. We’re about to overreact.”

Long offered this advice to Zuckerberg: “You’re the one to fix this. We’re not. You need to go home and right your ship.”

In the near term, such unilateral corporate action — reminiscent of the longtime Washington expectations that tech companies would “self-regulate” — may be the best chance for action toward limiting the collection and abuse of the user data produced by Americans.

Silicon Valley avidly watched both days of Zuckerberg’s congressional testimony as it streamed live online from the opposite coast. While many praised his largely cool and knowledgeable performance, tech executives also braced themselves for a new, more aggressive approach to regulation.

Some already were looking for ways, as Facebook has, to comply with expected new requirements before they become law. Others were trying to game out the winners and losers in legislation that almost certainly has not yet been written, much less debated or voted on.

“I am pretty certain we are going to see an onslaught of regulation,” said Om Malik, a technology writer and partner at True Ventures, a Silicon Valley venture capital firm. “It will be shaped by people who can spend the most on lobbyists. Amazon, Google and Facebook for example. I think it is not a surprise they welcome regulation. It will prevent small competitors to amass data, develop algorithms and gain an advantage over these three companies in advertising and commerce.”

Even if Congress does not soon pass any new bills to regulate technology companies, experts said they expected restrictions from Europe’s new data privacy law, which takes effect next month.

The new law, called General Data Protection Regulation, requires that companies get explicit consent from users for every possible use of their data — or face fines of up to 4 percent of global profits.

In the Capitol Hill hearings, Zuckerberg said that Facebook has been making changes to respond to the European rules. The company also announced last week that it was simplifying its privacy controls.

“All the same controls will be available around the world,” Zuckerberg said Wednesday. He confirmed that Facebook would comply with the European rules no matter where users live — a key priority for American privacy advocates who see this move as a step toward U.S. government regulation.

Zuckerberg also reiterated Facebook’s endorsement of a bill, the Honest Ads Act, that would require new transparency in online political advertising, in response to the Russian disinformation campaign that aimed to shape the outcome of the 2016 presidential election. Such concessions are rare for Silicon Valley companies that have fiercely resisted interference from Washington.

Wednesday’s House hearing was both sharper in tone and faster in pace than Tuesday’s Senate hearing. With four-minute limits for each of more than 50 committee members, the event often had the feel of speed dating gone wrong, with a grim-faced Zuckerberg rapidly questioned across a wide range of topics and often being interrupted before he could frame a full answer.

On many occasions, House members demanded that he stick to a simple “Yes” or “No” — and more often than not, he complied.

Exiting the hearing, the panel’s chairman, Rep. Greg Walden (R-Ore.), signaled that his inquiry is only beginning. “I don’t want to rush into legislation minutes after having the first hearing of this magnitude. But certainly if they can’t clean up their act then we’ll clean it up for them,” Walden told reporters.

A day earlier, fellow Republican Sen. John Neely Kennedy (La.) issued a warning of his own: “I don’t want to vote to have to regulate Facebook, but by God I will,” he said. He later told Zuckerberg, “Your terms of service suck.”

A Gallup poll released this week showed a sharp spike in concern about how Facebook handles its users’ privacy. Yet as levels of public concern grow, even lawmakers who are eager to demonstrate progress are wondering aloud what they can manage in the current political environment.

“I’m pessimistic [regulation] happens with a Republican majority,” Rep. Frank Pallone Jr. (N.J.), the ranking Democrat on the Energy and Commerce Committee, told reporters after the hearing. “But we’re going to keep pushing . . . and if we’re in the majority next year, we’ll push all the more and try to do it.”

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