Back in the early 2000s many commentators were still marvelling at the freedom of the internet and its democratic potential when the US legal scholar Cass Sunstein offered a stark warning.

This virtual Wild West, he said, might allow us to overcome some of the social and geographical barriers between people, so that we establish a more balanced view of the world around us. But it was equally possible that we would simply erect new fences, as like-minded people siphon themselves into homogenous groups who all share the same viewpoints and gather their information from the same sources.

“Although millions of people are using the Internet to expand their horizons, many people are doing the opposite, creating a Daily Me that is specifically tailored to their own interests and prejudices,” he wrote. They would, in effect, live in ‘echo chambers’, leading to greater polarisation in a country’s politics.

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Later commentators embraced the idea, while also pointing out that the technology platforms themselves may drive a further wedge between the different groups. Facebook and Twitter, for instance, may work out that you are more likely to click on shared stories from the New York Times rather than the Daily Mail, and so preferentially promote those stories on your feed.