This month, Congress is considering whether to pass legislation intended to combat sex trafficking online. It may sound like a worthy goal, but it would undermine a more than 20-year-old law that has been fundamental to today’s internet. If only the members of Congress would remember the old adage: If it ain’t broke, don’t fix it.

But the internet is sort of broken, you might think, given the very real problems [1] of harassment, hate speech, fake news, and other issues you may think we have with social media and big internet companies. Maybe any change in the law to make Facebook, Google, and other tech companies more responsible for bad content is a good idea.

Sadly, the intuitively appealing approach is wrong. If Congress follows through and passes this legislation, it not only will fail to achieve the bill’s stated goals—it also will fundamentally change, and arguably cripple, the internet you’ve grown to rely on these past two decades. If you’re going to call your members of Congress—and by all means you should—it’s worth understanding both problems.

There are two legislative frameworks in conflict here. The first is the Communications Decency Act—specifically, Section 230 of it—which was passed in 1996. It protects internet platforms (generally but not universally) against legal liability for acts their users commit. The second is something the Senate is set to consider in the next few days: the Stop Enabling Sex Traffickers Act, which would undermine Section 230 and its central role in giving birth to today’s internet.

If the bill passes, the best a would-be Facebook killer could aim for is to be a better Prodigy.

Introduced by Republican Ohio Sen. Rob Portman, in August of last year [2], the first version of SESTA was designed primarily to make it easier for plaintiffs and state attorneys general to sue Backpage.com. And support for the bill has been fueled by an effective (if disingenuous) documentary called I Am Jane Doe [3]. SESTA, in an amended version, was reported favorably out of committee in the Senate in January and set for the Senate’s regular legislative calendar. But the House wasn’t sitting idly by, waiting for the Senate to work its process—on Feb. 27, the House passed a bill (388–25) called the Allow States and Victims to Fight Online Sex Trafficking Act, or FOSTA. (This combined House version is also called the “FOSTA-SESTA package” [4] because an earlier version of FOSTA did not have elements of SESTA in it, as I’ll discuss in a minute. It’s worth reminding Congress that acronyms are supposed to make things easier to say and remember, not harder.) The House’s quick passage of its bill has set the stage for the Senate to vote on the mushed-together FOSTA-SESTA in the next few days—I say “mushed together” because the House bolted the broad pro-plaintiff provisions of SESTA onto FOSTA, leading to what one commentator has called “a FOSTA + SESTA Frankenstein combination [5]” that “takes the most plaintiff-favorable pieces of FOSTA and SESTA and creates a superset of both bills’ worst provisions.”

Writ small, SESTA and FOSTA have always been ostensibly about sexual services offered on online classified-ads platforms like Backpage.com (expressly a target of the bill) and Craigslist (not officially a target)—especially if the services involve sex trafficking or victimization of children. (What tends to get overlooked is that even if SESTA never passes, Backpage is likely subject to criminal and civil penalties, as a Senate committee report [6] argued last year. The Los Angeles Times noted this report when it editorialized [7] against SESTA just last week.) But the legislative language is written broadly enough to reach online services that aren’t classified-ad platforms of any sort—it appears to apply to public and private online forums and even emails and direct messages. Some observers, including me, think this breadth is intentional—some companies and industries with their own beefs against internet companies want SESTA to be enacted as a precedent to whittle away other protections for internet services.

There have been efforts to improve SESTA since I wrote about it in Slate last year [8]. One amended version did include some slight improvements, although it still created perverse incentives for service providers to censor the content you post or to turn a blind eye to all content, even if illegal. The House counterpart, FOSTA, was originally more narrowly tailored. Although it had its own flaws, FOSTA at least targeted companies and individuals that were intentionally facilitating sex trafficking and related activities. Internet-law experts have been arguing against any law that alters the framework set up by Section 230, but many believed that in that form, FOSTA would have done comparatively less damage, thanks to its being limited by a strict criminal-law “intent” requirement. (In short, you’d be found “guilty”—that is, liable in a civil lawsuit—only if a jury believed you actually intended to facilitate sex trafficking with your online service.)

Internet policy experts hoped that, at minimum, that clean version of FOSTA would replace SESTA. What happened instead is the FOSTA-SESTA package, in which House lawmakers have incorporated the worst provisions of both bills in ways aimed at making internet companies more subject to prosecution and lawsuits and more prone to censor users’ speech online. This combined bill has consequences not just for the companies but also for those who use these companies’ services. As Emma Llansó of the Center for Democracy and Technology puts it,

The practical result of this legal risk for intermediaries will be broad-based censorship. Smaller platforms will also face the real risk that a single lawsuit could put them out of business. This bill jeopardizes not only classified ads sites but also dating apps, discussion forums, social media sites, and any other service that hosts user-generated content.

And those are just existing services. The law will also affect future services, both those offered by the established, successful, giant internet companies and those from future startup companies that might hope to compete with the giant incumbents. Section 230 may have given us Google and Facebook, but a calamitous alteration or even outright repeal of Section 230 might not kill any company of their scale. After all, they have plenty of money in the bank and perhaps could adapt over time to all the additional costs of beefed-up monitoring, censorship of content, and the many more lawsuits they’d have to defend against. (Even keeping in mind that they wouldn’t win all those cases—there’d likely be big payouts to at least some plaintiffs and state attorneys general as well.)

But new companies, which might otherwise hope to compete with Facebook, Google, or other big tech incumbents someday, wouldn’t be able to afford the costs of compliance and legal defense. They’d likely face the hard choice of either supercensorship (yank anything users say or post that seems even remotely likely to pose legal risk) or just abandoning the startup project altogether. (Internet-law experts refer to this as “the moderator’s dilemma [9].”) A would-be Facebook killer wouldn’t be able to compete by being a better Facebook—the best it could aim for is to be a better Prodigy. Prodigy, the original “walled garden” of online services, was an early competitor among online companies, with its forums highly moderated by its staff—you couldn’t post your content publicly on the service without subjecting your postings to screening by Prodigy editors. Unsurprisingly, Prodigy in its original form [10] didn’t do well in the long run competing initially with more open, less moderated services like AOL and CompuServe or, ultimately, with the offerings of the wide-open internet itself.

Alternatively, a would-be internet service company might try instead not to monitor its service or enforce policies against objectionable users’ content at all, so as not to risk triggering liability based on “knowing” or “intentional” facilitation of sex trafficking or illegal sexual services. Here the model would be to create a company that operates something like a telephone service provider—telephone companies don’t censor their users’ content but also aren’t liable for what users say over the telephone. Of course, when you offer a service modeled after the phone companies, you may not be competing with Google or Facebook, but you’re almost certainly competing with AT&T and Verizon, not to mention the cable and internet companies.

But I’ve been emphasizing FOSTA-SESTA’s harms to companies—what matters even more is what FOSTA-SESTA would do to you and your personal use of the internet. Nowhere is the potential impact of the new law better framed than in this summary [11] by internet lawyer Cathy Gellis:

It isn’t just the big commercial services like Facebook who need Section 230, but Internet service providers of all sorts of shapes and sizes, including broadband ISPs, email providers, online marketplaces, consumer review sites, fan forums, online publications that host user comments. … Section 230 even enables non-commercial sites like Wikipedia. As a giant collection of information other people have provided, if Section 230’s protection evaporates, then so will Wikipedia’s ability to provide this valuable resource.

I know, I know, you’re probably saying, this is just an updated version of the ancient “Imminent Death of the Net Predicted [12]” meme. I wouldn’t go quite so far—after passage of SESTA, we’ll likely have some kind of internet left. It just will be a less open, yet less safe version of the internet. Less safe? you’re now wondering. Yes, less safe not just for everybody (because it’ll be less easy for us to talk to one another) but also for the same class of people SESTA supposedly is aimed to protect. (See “ ‘Sex Trafficking’ Bill Will Take Away Online Spaces Sex Workers Need to Survive.” [13])

The fact is, this latest version of FOSTA-SESTA is so badly, hastily, and sloppily crafted that even the Department of Justice, which makes no secret of wanting to expand its enforcement and maybe see more limits on Section 230 protections, thinks FOSTA-SESTA is less than fully baked. (Take a look at DOJ’s firm-but-respectful letter [14] offering the department’s assistance to make a bad bill better.) The Justice Department is fairly nice in spelling out what’s wrong with the bill, but you can supplement the letter with other experts’ and lawmakers’ take on FOSTA-SESTA as summarized by Mike Masnick at Techdirt: “DOJ Tells Congress SESTA/FOSTA Will Make It MORE DIFFICULT to Catch Traffickers; House Votes for It Anyway [15].”

There’s no reason to be particularly hopeful that Congress will come to its senses and at least give FOSTA-SESTA another look. But that’s no excuse not to try to move the needle anyway. If you want to get involved, the Electronic Frontier Foundation has a take-action page [16]. The internet’s not perfect, by any means, but it means enough to most of us that we should ask Congress not to screw it up in the course of trying to make it better.