In those earlier times, surveillance wasn’t particularly profitable, but over the last two decades, new technologies coupled with new theories of value have transformed the economics of privacy. A drastic decrease in the cost of mass surveillance (thanks to the internet) has increased the value of two types of asset: our data and our attention. The race to maximize those assets by companies big and small has made surveillance a growth industry. It is in this sense that capitalism has begun to change sides.

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You can, of course, still make plenty of money in more traditional ways. But the richest companies in the world now generate wealth by putting as many trackers, devices and screens inside our homes and as close to our bodies as possible. Accumulated data creates competitive advantage, and money can be made by consolidating everything that is known about an individual.

This business model was pioneered by Facebook, Google and the online advertising industry, but other sectors of the economy now want in. Amazon is a convert, as are cable and telecom companies like Comcast and Verizon, as well as the electronics industry with its “smart” devices that spy as they serve. Many employers also now constantly watch their employees. There is good reason to believe that, if nothing is done, gratuitous surveillance will be built into nearly every business and business model.

Some have argued that there’s no need to be concerned. After all, even in an age of constant surveillance, we’re talking about being watched not by the secret police but by advertisers and other commercial enterprises. This “spying,” the argument goes, only makes products better and advertisements more “personalized.” The end result is selling people stuff, not sending them to Siberia.

But this argument ignores several hard truths that we have learned in the last decade. One is that data and surveillance networks created for one purpose can and will be used for others. You must assume that any personal data that Facebook or Android keeps are data that governments around the world will try to get or that thieves will try to steal.

A similar lesson can be drawn from the Cambridge Analytica scandal. Facebook collected information from millions of users for one set of purposes, but Cambridge Analytica, a political data company working for Donald Trump’s 2016 presidential campaign, used that information to try to influence American voters.