Facebook sees itself as a commercial firm, not a social institution, and behaves accordingly. It makes money based on the depth and scale of its users’ data. That is why no one should be surprised that a former executive from the controversial data-mining firm Cambridge Analytica claimed in parliament that it had used harvested data from a much greater number of people than the 87 million users previously thought. If data is the new oil, then Facebook has one of the biggest reservoirs of black gold. Cambridge Analytica, it might be argued, tapped a rich well of information.

Yet the scale of the data that was extracted without anyone noticing exposed as hollow the idea that users could control what was done with their personal details. In today’s world, information is accessed in complex, hidden ways: by data-sharing, third-parties, via friends. The risk is that we don’t know what it is we are authorising. Facebook says it has closed the loopholes by which so much data leaked and is now asking users to opt in to new features. Yet it is still not clear what we are consenting to in sharing personal data, and whether the terms on which the consent was given can be enforced.

This raises big questions about how information is being organised in a democracy – and what purposes it is being used for. The collection and use of data – and the profiting from this – ought not to undermine citizenship. Democracy rests upon the idea that voters have agency; that they are not just being exploited by propaganda machines. Facebook’s surveillance capitalism is built to obtain personal data about individuals and their habits so that advertisers can shape the way information is presented to them and persuade them to act. What makes Facebook so dangerous to democracy is its business model.

Facebook has realised this – and that the public has become aware of its threat. The company rebranded its philosophy: it wants now to bring the world “closer together”, because in acquiring 2 billion users it has fostered divisions. The social media site is exploited by conspiracy theorists, white supremacists, hyperpartisan news sites, eastern European troll farms and Russian-backed divisive advertising. These seek to manufacture and retail a point of view by manipulating voters’ fears – and their dreams.

The conceit of data mining firms – and the politicians who use them – is that they could win elections by moulding electorates based on new forms of identity and new value systems. This process is accelerated by the echo chamber of social media, which allows citizens to close themselves off from wider debate and become infatuated with their own truths. There is room for interesting ideas and alternative narratives based on facts. Diversity is the sign of a healthy ecosystem. But democracy will suffer if tech giants can exercise near monopoly power over data, with hardly any accountability about how this power is used. It needs all citizens to listen to each other, so collective decisions are considered decisions.