Whatever happened to the mythical American neighbourhood, that Rockwellian idyll of friendliness and normality, where no problem cannot be resolved by the community spirit, and nothing nasty ever happens?
The scarcely believable tale of the three girls kidnapped and held for a decade in a house on an ordinary street in Cleveland, Ohio, raises many questions. It's hard to imagine they didn't have chances to escape the clutches of their single jailer Ariel Castro and end their ordeal sooner. Or did some form of Stockholm syndrome bonding develop between Castro and his victims, Amanda Berry, Gina DeJesus and Michelle Knight?
Nor do the Cleveland police emerge with much glory from the affair, having apparently failed to react even to reports of a naked woman on all fours and in a dog collar in Castro's back garden.
But the biggest mystery is the neighbours. How on earth did they see nothing amiss for so long, and not raise the alarm?
Here, in America, such things are not supposed to happen. In the inner cities maybe, but not in the suburbs, where streets hold annual block parties, where local kids sell lemonade on the corner in the summer, and where the internet now provides an additional clearing house for local news and gossip. All of the above are facets of the US neighbourhood community which, when written about, almost automatically comes with the adjective "tight knit".
This is, moreover, the land that invented Neighbourhood Watch, the system of local security that - as shown by the notorious case of Trayvon Martin, the Florida teenager shot dead last year by a Watch co-ordinator on suspicion of being a criminal intruder - can on occasion in the US verge on downright vigilantism.
Move to America and the sense of neighbourhood is far more palpable than it is in Britain, at least in my experience. In London, we knew a few people on our street. Here, in Washington, you feel you know everyone. That comforting, reassuring term "community" permeates American society.
Send your child to the local school - in our case, Lafayette - and you are part of the Lafayette community. You can be part of the disabled community, the gay community, or any particular interest community. Often they have strict rules. If you live in some gated community, woe betide you if you paint your house the wrong colour, or fail to mow your lawn.
And the pattern extends to the political system, dominated by special interest groups of every hue. From healthcare to banking reform to gun control, every piece of major legislation that comes before Congress is a battle between lobbies and interest groups - in other words, "communities". The National Rifle Association may be a fearsome organisation. Less so perhaps when you think of it as the "gun-owning community".
Myself, I've always wondered whether this habit can be traced in part to the German input into the collective American psyche. It is an often overlooked fact that Germans, not Italians, Irish or English, constitute the largest single ancestry group in the US. I lived in Germany for three years in the 1980s, and an abiding memory is of the nosiness of neighbours, well-meaning but based on the belief that a person must behave according to local community norms. However, I digress.
Cleveland has somehow given the lie to all this. If communities are supposed to look after their own, this particular one failed. Of course, not everywhere is the same. I live in white and prosperous north-west Washington DC, Castro on the poorer west side of Cleveland, in a neighbourhood where many people were of Puerto Rican origin.
Even so, maybe if they had done what they were supposed to do, and had the police followed up more thoroughly, Castro's crime would have been exposed far sooner.
Moreover, so awful was that crime that no one on the street could have imagined it. When you move into a new neighbourhood, you tend to assume the people next door are OK. When you see them digging in their garden, you don't think of serial killers disposing of their victims. Yes, 100-odd children are kidnapped in America in the average year. But even when a house is kept locked, and you can't see in, your immediate suspicion is not that three of those children are inside, prisoners being abused, even tortured.
Charles Ramsey, the neighbour whose colourful account of his rescue of Amanda Berry has turned him into a national cult hero, makes precisely that point. Ramsey had lived next door to Castro for a year, but suspected nothing strange. Insofar as they were aware of the girls, he and others on the street seem to have assumed they were Castro's grandchildren. As for the rescue, he said in one of many interviews he dispensed to TV networks in the 48 hours that followed the news: "I'm not a hero. I'm a Christian and an American."
In other words, so far so good for the conventional image of local community life in the US. "Everyone on this street knew each other," Ramsey told another network. "I give this dude his mail when it comes to my house. I eat his food when he feels like barbecuing. When he feels like playing salsa music, I try to merengue." He had not the slightest inkling of the horrors inside.
"Had I known [he kidnapped the women], well, this would be a whole different interview, wouldn't it?" But Ramsey didn't know. In the absence of knowledge, the truth that finally emerged was simply unimaginable.
Perhaps we expect too much of the American neighbourhood. Even in the closest-knit community, not everything is shared. The story from Cleveland - horrible, incomprehensible, redeemed only by its happy ending - is proof that no human being, least of all the person over the garden fence, is ever completely knowable. And thus it has always been. There are many amazing things but none more amazing than man, wrote Sophocles in his play Antigone. Or, as they still say in Lancashire, there's nowt as queer as folk.