I’VE always been wary of that “sign up with Facebook” button when I stumble upon an app or a website that requires authentication. Why do they all want me to go through Facebook? I was right to decline these invitations, because as we now learn that OAUTH, or Open Authorisation, is one of the many ways that Facebook and the app developers conspire to access not only your data, but that of your friends and contacts.

I thought I knew a bit about the practices of social media behemoths, but it was only through the recent coverage of the data “breach” that I discovered just how much you sign away when you sign on with Facebook, or Twitter or Google. These people do nowt for nowt. I put “breach” in quotes because the revelation that Cambridge Analytica was able to use personal data of 50 million people in its efforts to get Donald Trump elected was not the result of an actual leak or a hack. In fact, it is a special example of the data mining that happens routinely on social media.

As the saying goes, if you aren’t paying for the product, you are the product. Facebook sells our data to private companies, or allows them to harvest, for use in targeted advertising, the vast treasury of information that we voluntarily post on these sites. Politicians, always on the lookout for clever marketing techniques, soon realised that this was a way of targeting political messages more accurately than had ever been achieved by conventional TV advertising or mailshots.

Even Barack Obama’s presidential campaign in 2012 used data mining not unlike that deployed by Cambridge Analytica. When people signed on as Obama supporters via Facebook they allowed access to information about their friends. Unlike the Cambridge Analytica breach, this was in accordance with Facebook’s rules, and did not breach data protection laws, but it is a moot point whether everyone who signed on realised how much data they were giving away.

We live in a sea of manipulated information. Facebook and Google have become two of the most valuable companies on the planet by discovering that data is the crude oil of the 21st century. Following the Facebook motto of “move fast and break things” they didn’t stop to think what uses might be of their digital toys. They assumed that getting people to sign away their rights by appending lengthy and largely incomprehensible legal documents to every digital portal would make them immune from the law or regulation. They aren’t, as Facebook is about to discover.

Yesterday, the UK Information Commissioner, Elizabeth Denham, sought a warrant to investigate Cambridge Analytica (CA) for alleged misuse of digital data derived from Facebook. She also sought to bar Facebook researchers, who are also investigating CA, from the premises in case they compromised the investigation. This is getting serious. There has been a clear breach of trust between regulators and the tech companies. The move followed the revelations in a Channel 4 report which suggested that Cambridge Analytica might have been using its resources to compromise politicians, not just by stealing their data, but by staging honey traps and covert video stings. Cambridge Analytica insists it has been misrepresented and does not engage in these activities.

What is not in doubt is that the political marketing firm acquired its vast trove of information from a Cambridge University academic, Aleksandr Kogen. He had harvested personal data by means of an apparently innocent personality quiz. As people signed on to the app using Facebook’s authentication, they inadvertently released data about themselves and their friends; 270,000 took the quiz, but Mr Kogen gained access to 50 million friends and contacts, mainly in the US, which is why it was so useful to the Donald Trump campaign.

Now, if you follow this story on social media you will find no shortage of tech gurus insisting that this is just what Facebook and countless data mining companies do all the time: scrape personal data off social media sell it to private companies. Nothing to see here. Move along. But while data mining may be old hat to the techies, it isn’t for the millions of users of these applications who are only now becoming dimly aware of what’s been going on. Techies assumed that the non-computer literate “sheeple” are okay with all this because no one has complained. Well, we emphatically are not. The fact that this has been going on for a long time just makes it more shocking. These firms have been exploiting our ignorance. The public, and the regulators, are finally waking up.

But there is more to this than hoodwinking the consumer: for the techies have been hoodwinking themselves. As in the financial crash, the tech companies like Facebook and Google have been dabbling in digital processes they don’t fully understand. Facebook’s secret algorithms have been spreading fake news, creating filter bubbles, promoting prejudice and facilitating abusive behaviour. Nation states, political parties and malign organisations like the Russian Fancy Bears have been manipulating Facebook in ways which Mark Zuckerberg never imagined.

Google has been spreading sick video parodies of Peppa Pig to children through YouTube’s video autoplay feature. Its owners clearly never imagined that their video-sharing website could be used in this way. Google was also discovered selling advertising around hate preacher videos and Islamic State recruitment sites. Larry Page and Sergey Brin’s original Google mission statement said: “do no evil”, but their algorithms don’t understand moral philosophy, and see no problem promoting videos claiming that the Florida school shootings were staged by actors as part of a conspiracy by the deep state and Jewish bankers. Give the people what they want, is the algorithmic code.

The masters of the tech universe have been too clever by half. They have blinded us by science and fooled themselves with their own hype. They have done serious damage to our public sphere, made a nonsense of privacy and created a series of devastating feedback loops. This can’t go on. Social media is about to meet its regulatory nemesis. Or to extend Mr Zuckerberg’s metaphor, if you break it you pay for it.