(Bloomberg) -- Democratic 2020 contender Elizabeth Warren’s call to break up big tech companies like Facebook Inc. and Amazon.com Inc. thrust into the mainstream an emerging movement that favors an aggressive attack on corporate power.

Warren’s proposal last week to classify some technology giants as utilities and undo previous industry mergers jolted Silicon Valley. It also hit a nerve among Democrats and Republicans in Congress, who’ve grown increasingly concerned that curbs on anticompetitive conduct are poorly enforced.

That all but ensures that restraining the power of dominant companies will be a focus of the 2020 campaign as Democrats seek to unseat President Donald Trump. Later this month, presidential candidates Amy Klobuchar and Julian Castro are set to appear at an Iowa event along with Warren to discuss monopoly power in rural communities.

Still, Warren’s prescription for targeting big tech is not without political and legal risks. Breaking up a company would entail years of litigation and could alienate some voters who enjoy its services. And even advocates of reining in big companies aren’t necessarily on board.

"Elizabeth Warren’s proposal is very radical because it’s front-running the intellectual debate rather than codifying what the intellectual debate has produced," said Luigi Zingales, director of the Stigler Center at the University of Chicago. "The people who think there is a problem are probably in the minority, even in the academic world."

Rethinking Enforcement

Warren’s broadside is part of a wider rethinking of antitrust enforcement in the U.S. that until now has has been mostly relegated to legal conferences and academic papers. At its heart is the view that antitrust officials have fallen down on the job, leaving broad swaths of the economy dominated by large firms insulated from competition. Plenty of lawyers and economists dispute there’s a problem, but its proponents have pushed the break-em-up idea to center stage in the antitrust circles of Washington and academia.

There’s a split on how to deal with the issue. One view, advanced by Barry Lynn’s Open Markets Institute in Washington, calls for throwing out the current playbook and reorienting antitrust enforcement away from its emphasis on consumer prices. Lynn advocates for reining in the ability of big platforms to squeeze sellers. One way to do that -- which Warren embraces -- is prohibiting tech platforms from moving into different lines of business where they can abuse their power as middlemen.

Balanced Approach

Another camp supports stepped-up enforcement under the existing framework based on consumers. That’s a balanced approach that was articulated at a conference last week in Washington that featured former Justice Department and FTC officials. It’s an approach Warren would reject, said William Kovacic, a former FTC commissioner who is now a professor at George Washington University Law School.

"She’d say, ‘it’s nice and it’s cute, but you guys don’t have the guts or the vision to see what has to be done and I do and everything that went on in here is a timid response to a serious problem, and the house is burning down and you still want to water the bushes in the back yard,’” Kovacic said.

Warren’s not alone in favoring a more aggressive approach. Joe Simons, the head of the Federal Trade Commission, has acknowledged the possibility enforcers may have fallen short. He set up a task force last month to investigate tech companies and possibly unwind past mergers. The chairman of the House’s antitrust panel, Democratic Congressman David Cicilline said earlier this year that when it comes to tech companies, "every option is on the table."

Existential Threat

Talk like that would have been dismissed as fanciful just a couple of years ago when Silicon Valley was the darling of the Obama administration. Now it’s grappling with what increasingly seems to be an existential threat. And it’s coming not just from liberal Democrats like Warren and Senator Bernie Sanders. Even Republicans are on the attack. Senator Josh Hawley of Missouri told the Conservative Political Action Conference this month that Facebook and Google are "a law unto themselves" and are threatening competition. Senator Ted Cruz of Texas even retweeted Warren, saying she was right to criticize Facebook for having too much power.

Warren has called for legislation that would treat large tech companies like Amazon as utilities and ban them from owning participants on the platform. Under that scenario, Amazon’s marketplace, for example, would be split from its AmazonBasics business. Google search would be spun off from the rest of the company. Warren also said she’d seek to undo past mergers that she said undermined competition, including Facebook’s acquisition of Instagram and Google’s purchase of DoubleClick.

Breaking Up

Preventing tech platforms from moving into other lines of business -- also called vertical integration -- is an idea backed by Lina Khan, an antitrust scholar who wrote an influential paper on Amazon’s threat to competition. Khan, who was recently hired to work for the House antitrust subcommittee, lauded Warren’s proposal. She argues that separation addresses the risk that technology platforms like Amazon and Google will discriminate against companies that depend on them.

Breaking up companies is practically unheard of today in antitrust enforcement. The last example occurred in 1982 when AT&T reached a settlement with the Justice Department to give up its local phone companies. Nearly 20 years later in the U.S. antitrust case against Microsoft Corp., a federal judge ordered the company split up, a decision later reversed on appeal. Warren, like many others, credited the Microsoft case for paving the way for Google’s success.

Policing Platforms

Since then, U.S. enforcers don’t have much to show when it comes to policing tech platforms, while European officials have brought antitrust cases against Google and Facebook. The FTC and Justice Department are frequently criticized for approving mergers that allowed Facebook and Google to strengthen their dominance. In 2013, the FTC under President Barack Obama closed an investigation into whether Google violated antitrust laws by skewing search results.

Some experts are still mystified by that decision.

"Why didn’t you pull the trigger? You had the shot," Kovacic said. "That’s what they have not answered for us."

Bringing a case today to force a breakup of a tech company (let alone three of them) would require years of litigation and face a skeptical judiciary, according to Kovacic. Last year, the Supreme Court ruled against a group of states and the U.S. in an antitrust case against American Express Co. that some saw as hobbling enforcement against tech platforms.

Political Risk

And there’s a risk Warren’s proposal will alienate some voters, given that people understand the benefits the companies provide, said Daniel Crane, a professor at the University of Michigan Law School. While her vision will find support among liberal Democrats, Crane said, it also resonates in some quarters on the right. Former Trump adviser Stephen Bannon reportedly supports regulating Google and Facebook like utilities.

"The question is how deep will the political support be for the kind of very aggressive change in direction that Liz Warren is pushing," said Crane. "Will she ultimately get traction and will it turn into votes? I’m a little skeptical that’s going to happen for her."

To contact the reporter on this story: David McLaughlin in Washington at dmclaughlin9@bloomberg.net

To contact the editors responsible for this story: Sara Forden at sforden@bloomberg.net, Paula Dwyer

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