Note to government bureaucrats panting to regulate Facebook: Back off! And that’s from someone who is no fan of the social media giant.

As the Cambridge Analytica scandal unfolds, politicians and government officials in the U.S. and England are itching to pounce. Fueled by Facebook’s repeated disregard for customer privacy and its link to the campaign of Donald Trump, legislators are eager to stamp out the company’s ability to harvest user information for profit.

This poses a threat to Facebook and its social media rivals, who depend on that harvesting for their livelihoods.

It is also an altogether useless undertaking. Government regulators are not up to the task. After all, Facebook had already entered into a consent decree in 2011 with the Federal Trade Commission guaranteeing user privacy, and in 2015, it amended its policies to prevent just such problems. That didn’t pan out so well.

Government restrictions will not only prove pointless but could well undermine the forces that will ultimately bring Facebook and its rivals to heel: competition. In the last quarter, the number of daily active North American users on Facebook declined for the first time ever.

Why? Maybe it was disgust with the company’s sloppy distribution of fake news or concerns about Facebook’s efforts to censor material.

More likely, it was because people had moved on to Instagram (which Facebook owns), YouTube or another site. If people care about their privacy (and it’s not at all clear that they do), they will gravitate to a service that offers better protections.

That could include a free app like Signal, which permits encrypted texts, phone calls and video chats between users and is ad-free. If such services become more popular, Facebook will have to change its ways.

Rivals will rein in bad behavior from Facebook, not new rules, and it is that potential leash that regulators might destroy.