In books and movies that pack a wallop you will usually find a “charged object” – an item crucial to the plot and freighted with emotion. The slipper in Cinderella. The apple in Adam and Eve. And today, in the story of what has gone wrong with childhood: the smartphone.

It’s not that phones aren’t a real problem. We have all seen it. Kids glued to their phones in a restaurant. Kids glued to their phones at the bus stop. The other day I saw a girl swinging on a swing – the classic summer pastime – glued to her phone. And oh, the content! This study alone will give you pause: ParentsTogether Action reports that children see sex and drug content every few minutes on Snapchat. If only we could take away their phones, a happy childhood would be restored – or so it can seem.

But there is another crucial object that is so not charged, so unsexy that it is barely noticed at all. It is the front door. Take away the phone and open the door – that’s when childhood changes. Just taking away the phone does not do the trick.

Currently, as children look forward to their summer breaks from school, most of their doors are sealed like safes. An Institute for Family Studies survey of 24,000 American parents asked what age they let their kids walk around their neighbourhoods. The majority said they wouldn’t even let them leave the block – at age 14.

In the UK, meanwhile, a classic article, How children lost the right to roam in four generations, chronicled the childhoods of one British family, beginning with the 88-year-old great-grandpa: “When George Thomas was eight he … regularly walked six miles to his favourite fishing haunt without adult supervision.” The walking range of each generation keeps shrinking until we get to George’s eight-year-old great-grandson, who “enjoys none of that freedom. He is driven the few minutes to school, is taken by car to a safe place to ride his bike and can roam no........

© The Guardian