Often, decades pass between a harm appearing and societies fighting it. Scientists knew by the 1950s that smoking killed. The UK finally banned children under 16 from buying cigarettes in 1986. Now an international movement is belatedly forming to stop kids from ingesting another toxin: social media. After Australia’s pioneering ban on its usage by under-16s last year, countries including Indonesia, Switzerland, the Netherlands and France are considering bans for children. The case seems unarguable. Social media have worsened teens’ mental health, empowered criminals and shattered people’s concentration to the point of making the world stupider.

Don’t take it from me. Take it from social media companies, which, like tobacco and oil companies, realised before the public what harm their products do. An internal report by TikTok admits that compulsive usage “correlates with a slew of negative mental effects”. According to one lawsuit against the company, these include “loss of analytical skills, memory formation, contextual thinking, conversational depth, empathy, and increased anxiety”. Oh, and TikTok also damages “sleep, work/school responsibilities, and connecting with loved ones”.   

The quotations above and those that follow from TikTok and Snap (owner of Snapchat) were compiled by Jonathan Haidt from legal cases against the companies. Haidt, a social psychologist and author of The Anxious Generation: How the Great Rewiring of Childhood Is Causing an Epidemic of Mental Illness, is campaigning internationally to end the “phone-based childhood”. He says childhood was transformed by a series of innovations starting with the smartphone. High-speed internet got children watching videos. Touchscreens enabled compulsive scrolling. Selfie cameras let girls post images of themselves, then wait terrified for “likes”. Videogaming, porn and gambling gave boys such dopamine hits that anything else they did felt boring.