Last Wednesday afternoon Kieran Rodney-Davies was stabbed to death near his home in Fulham by a gang of boys who wanted his mobile phone. He was only 15, about the same age as his attackers, and he was out on an errand for his mother.

At one moment she had a sensible, charming, funny, loving son and at the next he was bleeding to death in the arms of a weeping friend.

This is the nightmare of every inner-city mother in the country. We have sons who have been menaced and robbed and beaten, in streets both rich and poor, by children not much older than themselves, often just for the hell of it. The streets of London are not safe for teenage boys.

One might assume from Kieran’s name and address in a smart part of London that he was a child of privilege. In a way he was, in that he came from a good home and had been brought up to be kind and helpful and to stay out of trouble, and such a careful upbringing is a privilege these days, especially for a boy whose mother is a single parent and lives on a council estate.

However, the truth is his degree of privilege made no difference; there is a terrible equality about the dangers of inner-city streets today.

After my first feeling of immense sympathy for Kieran’s mother, my second feeling was one of fury. It seems scarcely possible that Britain’s inner-city streets have in less than 20 years been allowed to become so disgracefully dangerous with little or nothing to anticipate it, to stop it or even to protest.

These days 25% of all street assaults and robberies are thought to be carried out by people under 18, increasingly including girls. Such children carry out more than 50,000 muggings a year in London alone.

My son and his friends have been threatened and mugged and stalked constantly. The first time it happened to my son was in daylight after school outside McDonald’s in Notting Hill.

He was 12 at the time. The time that school gets out is becoming increasingly dangerous. Bad teenagers get let out from the restraints of school, such as they are. Other even worse teenagers are hanging round the school gates waiting to prey on the pupils.

It is hardly surprising that people who can afford to get out of the inner cities are doing so as fast as they can. It’s a mistake to call this white flight, although it is predominantly white at present. Strictly speaking, it is rich flight and responsible flight — middle-class flight. It is a racing certainty that ethnic minority parents who have enough money will very soon and very fast be joining the queue to the burbs. I imagine Kieran’s mother might very well have preferred to bring her son up in a safe, leafy suburb with a good school had she had the option.

Tony Blair’s latest proud new initiative — yet another one — disclosed on Friday, was to entice the middle classes back into inner-city state schools by promising new improved facilities and standards in new improved city academies. This is just silly.

What’s wrong with inner-city schools these days, as he must know, is not so much the schools — the ideology or the facilities or the funding or the teaching — as the pupils. White flight is the flight of responsible middle-class parents from feral, violent, illiterate schoolchildren, who will terrorise their own children and wreck their education. Such parents can hardly be expected to put a sticking plaster of middle-class morality on the gaping wound of social breakdown.

The notorious comprehensive where I live has an exceptional head teacher, who is rapidly improving it, plenty of money, dedicated teachers and wonderful facilities.