On the Pandora’s Box side of the equation, they dispense lies, spread hate, and destroy lives, and the lives of the young seem to be most at risk.

“Something must be done about it” is now the cry heard far and wide. That is not to be sneered at, because it means at least that politicians and others concerned with the welfare of young people now recognise that free societies face a terrifying, perhaps existential, problem: Mass communication channels that, unlike printed press and television, are not inhibited by manners, taste, editors, and common sense.

The owners of the planet-wide platforms refuse to accept the responsibilities placed on publishers by legislation, the result of which can be seen in online sewers of libel and obscenity. This is not what a free press is supposed to look like.

The first difficulty is that there is as yet no definitive measure of the extent to which screen use and anti-social media can damage the mental health of children and teenagers. Are the tragic cases of youngsters being driven to suicide one-offs, or the first signs of a growing pattern?

Next, we have yet to see the emergence of a consensus as to what needs to be done, or can be done, to bring platforms such as Facebook, which owns Instagram, and Twitter to order.

They have been asked repeatedly to exercise control of the content posted on their sites, and have repeatedly failed to do so, or at least do so efficiently and with some degree of consistency. Is it, in the real world, possible for networks the size of Facebook and Instagram, to edit the content it most certainly publishes.

Instagram has 1bn users. It carries 95m new postings — photographs, videos, and what passes for written content — each day.

What sort of algorithms, or how many people, would be needed to ensure that pictures and words likely to damage young people were monitored, assessed according to consistent standards, and if necessary taken down not after days and weeks but within minutes? Is it possible, or practicable, to place a legal responsibility on parents to ensure their children’s screen time is used safely?

What we have so far is a mélange of reports, theories, suggestions, initiatives, and regulations here and there that according to a recent study by British MPs adds up to a standards lottery that does little to ensure that children and teens are as safe as possible online. Instagram’s promises to clamp down on pictures that promote self-harming have been dismissed as too little too late.

Germany has schemes for flagging up potentially dangerous postings, but it does not apply to all platforms. There are no easy ways through this mess. But if we are to protect our greatest asset, our young people, governments must steel themselves to use the law — with punitive punishments — to make social media corporations end the wild west culture they have spawned.

Their threats of legislation have been ignored. Now they must do it.