With a gaggle of right-leaning internet figures and conspiracists trickling out of the White House this week, pressure is mounting on an extraordinarily potent sliver of legislation that most people have never even heard of.

That law, known as Section 230, provides a legal shield for internet companies hosting user-generated content. Without it, platforms like Facebook and Twitter would be legally liable for every single piece of content they host. That’s the crushing, collective legal liability of 500 million tweets sent each day. Every passing thought generated by Facebook’s 2.38 billion users. Every beat of the more than one billion hours of video YouTube users watch every 24 hours.

The law—which supporters and detractors alike view as the legal cornerstone of the modern internet—was created in 1996 as an amendment to the Communications Decency Act. It states plainly that internet companies are not the publishers of any user-created content they host.

In recent months, Missouri Senator Josh Hawley seized on Section 230, taking it up as a pet issue—a stance that he doubled down on during the White House social media summit.

In a speech decrying the “fake media,” Hawley highlighted Section 230 as leverage he and like-minded lawmakers could wield against internet companies.

“Google, Facebook, Twitter, they’ve gotten these special deals from government,” Hawley said. “They’re treated unlike anybody else. If they want to keep their special deal, they have to quit discriminating against conservatives.”

“Just came from the White House Social Media Summit where I had chance to stand alongside @realDonaldTrump and talk about why we need to stop Big Tech from discriminating against conservatives,” Hawley wrote after the event, followed by the hashtag #Section230.

Taking the stage after Hawley, Trump lauded his efforts to limit legal protections for tech platforms as “very important legislation” before going on to say he doesn’t trust tech companies to “self correct.”

Silicon Valley's critics—and everyone else with a timely agenda to push—know there’s blood in the water. From the fallout of revelations around Russian election interference in 2016 to escalating concerns around flourishing hate speech and algorithmic radicalization, it's been open season on tech platforms—and the criticism is coming from all sides.

Naturally, some of that criticism is bubbling up into legislative proposals. Hawley’s bill, known as the Ending Support for Internet Censorship Act, would strip away that legal shield unless companies prove they are “politically neutral” through an external audit, though it does not specify how neutrality would be determined. This idea, trading some kind of guarantee of political neutrality for legal protections, is picking up momentum on the right.

Section 230 itself is very short and makes no mention of political neutrality. “No provider or user of an interactive computer service shall be treated as the publisher or speaker of any information provided by another information content provider,” the law states in full.

Ted Cruz alluded to the same misleading line of reasoning during Mark Zuckerberg’s big appearance before Congress last year. Questioning the Facebook founder, Cruz demanded to know if Facebook believes itself to be a “neutral public forum.”

“The predicate for Section 230 immunity under the CDA is that you’re a neutral public forum,” Cruz added, incorrectly.

Devin Nunes jumped on the bandwagon earlier this year, announcing a theatrical $250 million defamation suit against Twitter for hosting tweets that Nunes claims defamed him. Section 230 shields Twitter and other platforms from that liability. White House summit attendee Tim Pool is another vocal Section 230 detractor.

However disingenuous, Section 230’s newest critics do have a template for dismantling the key legal shield. Last year’s passage of FOSTA, also known as the “Fight Online Sex Trafficking Act,” paved a path for amending Section 230—a route that its detractors are eyeing.

That bill’s passage last year demonstrated how amendments to the law can result in swift, web-wide changes, like Craigslist removing its entire section for personals ads. That mechanism for changing the internet’s rules appeals to lawmakers looking to punish tech companies—but has privacy advocates and internet companies on high alert.

When that bill passed the Senate, Senator Ron Wyden was one of only two votes against the legislation. The Oregon Democrat co-authored Section 230 in 1996, amending the Communications Decency Act with the provision that allowed internet-based business to flourish.

“The failure to understand the technological side effects of this bill… will be something that this congress will regret,” Wyden warned last year.

Still, not all tech-savvy lawmakers see Section 230 in black and white. In an interview with The Atlantic last year, Senator Mark Warner (D-VA) suggested a more moderate path, one that accounts for the outsized role social networks play in modern life without limiting speech in a heavy-handed way. In 1996, it was unfathomable that an internet company could grow to treat a $5 billion FTC fine like a slap on the wrist.

“The social-media companies fight any changes to Section 230 as if it will provoke the complete destruction of the public square,” Warner said. “Obviously, that is not the case. Because there have been changes. There have been changes around child pornography. And you can’t print how to make a bomb. Most recently, we’ve imposed restrictions around sex trafficking.”

Warner, who sits on the Senate Intelligence Committee, argues that Section 230 made more sense “before more than half of the American people were getting their news from Facebook.” Now, he sees Section 230 reform as a potential avenue to hold platforms accountable for modern ailments like coordinated disinformation campaigns and deepfakes.

With Republicans more interested in punishing their enemies in Silicon Valley than pursuing thoughtful reform, it’s hard to imagine a middle path. And the debate over whether tech companies are really neutral hosts or publishers at heart is far from settled—even within the companies in question.

Conservatives who want to dismantle tech’s legal shield will likely encounter pushback from business interests on the right. The day before the White House event, a coalition of right-leaning free market groups spoke out in defense of Section 230, anticipating a renewed round of attacks.

“Countless conservative voices benefit from the liability protections guaranteed by Section 230…” David Williams, president of the Taxpayers Protection Alliance, wrote. “The internet flourishes when social media platforms allow for discourse and debate without fear of a tidal wave of liability. Ending Section 230 would shutter this marketplace of ideas at tremendous cost.”

A repeal of Section 230 could have extremely far-reaching effects, both for internet users and the platforms they use. In an op-ed on Fox News, the lobbying group representing the collective interests of Google, Facebook, Amazon, Twitter and many other major tech companies, made its case against amending or throwing out Section 230. Those businesses believe that peeling back Section 230 would make their legal liability too massive. Platforms would dry up—and quickly.

“Eliminating the ability of platforms to moderate content would mean a world full of 4chans and highly curated outlets—but nothing in between,” Internet Association President Michael Beckerman wrote in a statement supporting the legal shield. He describes Section 230 as a “critically important law that’s made the internet as we know it possible.”

The Internet Association previously pointed out that stripping away the law would impact not only the tech platforms that some vocal conservatives seek to punish, but also content like Amazon reviews, Wikipedia entries, and Airbnb reviews.

“Internet companies are not biased against any political ideology, and conservative voices in particular have used social media to great effect,” Beckerman said.