We’re still at it. No fewer than 130 days since the disappearance of Madeleine McCann, the subject animates dinner parties, gets women talking to each other in the street, provokes rows within families. The returning home of the McCanns is just the most recent twist in a story which has, to an extraordinary extent, taken us over. It’s something we all have an opinion about. For four months there’s hardly been a day when the McCanns have been out of the news. And the suspicion that the Portuguese police are attempting to convert the McCanns from victims into villains has turned sympathy to downright partisanship.

Why are we obsessed? This is an extraordinary phenomenon. Is it a further example of the Diana syndrome – the mass transference of public empathy on to individuals we don’t know, made all the more creepy by our increasing alienation from the people we live next door to? Is it a symptom of the contemporary, unbalanced sentimentality about children? Is it – as hundreds of The Sun’s readers suggested to the paper’s former Editor, Kelvin McKenzie, when he wrote a column sympathising with the McCanns – an example of a kind of collective bias in favour of the middle classes? Scores of children disappear every year yet not one has received a fraction of the attention given to little Madeleine.

Personally, I think the public interest over this one child is extraordinarily heartening. It’s a sane human reaction to a case that brings home a child’s vulnerability. Of course, it helps that the McCanns have been steely and hard-hitting in their publicity campaign. It also helps that this particular child is blonde and blue-eyed. Not to put too fine a point upon it, if Madeleine had been an ugly girl, or her mother less photogenic, the temptation to replicate their image would have been less compelling.

Then there’s chauvinism. That this has happened to Britons abroad strikes a chord – as Gerry McCann remarked, “in a system you don’t know and don’t really trust, it’s incredibly frightening”. Moreover, the accusation of Portuguese police incompetence, inviting unflattering comparisons with Inspector Clouseau, has confirmed popular suspicion that, flawed as the police are here, they’re worse there. Now that – in the common take on events – the police are attempting to make scapegoats of the parents, national exasperation has turned this case into a them and us affair with the McCanns, as it were, the British team.

Yet the real reason why people care about Madeleine is fundamentally decent. Everyone who is fond of a child thinks, with a shudder, “it could be mine”. It’s one of those “there but for the grace of God” moments that has turned a personal tragedy into a national object lesson. And that collective compassion for a child is anything but shallow – it is people showing the best of themselves.

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