In the week when the word “yob” was banned by Scotland Yard because it might “alienate” teenagers and injure their tender feelings (oh boo hoo), Stevens Nyembo-Ya-Muteba, 40, was murdered by a gang of “youths” outside his flat in Hackney, east London.

Stevens, a married father of two little girls, was an émigré from the Democratic Republic of Congo to Britain, where he held down two jobs — delivering food for Tesco during the day, night portering at a restaurant in the evenings — to pay for his education. He was in the third year of a maths and finance degree at the University of Greenwich, having turned down a place at Cambridge so as to stay closer to home. A 17-year-old “youth” has been charged with his murder.

Stevens lost his life because he had had the temerity to ask the gang to keep the noise down after they broke into the communal area of the council estate where he lived. It was about 10pm. “Some of us have work in the morning,” he’d reportedly said which, as rebukes go, is both polite and mild. He was stabbed for his pains and left to bleed to death on a stairwell.

It has since emerged that Stevens and other residents had repeatedly urged the police and the council to do something about the appalling goings-on at the estate. “Prostitutes, smackheads, people having sex on the stairs,” one resident said. Another mentioned gangs of youths congregating in stairwells, taking drugs, urinating and trying to start fires. “The police and the council had been aware of it all for some time,” a relative of Stevens said last week.

I used to live in Hackney opposite two crack houses. The phone box in our road was regularly used as a (rather snug) boudoir by stoned — and not in a benign way — prostitutes. There were needles in the local park and crack-smoking paraphernalia littered the pavements. We were once woken in the night by two dozen armed police who explained that there had been a burglary and that the burglars, who had guns, had taken refuge on our roof.

I took my sons for a walk in the park a couple of days before we moved out of Hackney. It ended abruptly when we saw a young boy being cut down from a tree; he had tried to hang himself.

This in an area, by the way, which was last week described by a London newspaper as up-and-coming and made to sound rather charming and cosmopolitan, with bars and cafes open until 5am (I rather wonder who the paper thinks goes drinking at 5am. Schoolteachers? Yummy mummies? Or — here’s a thought — a feral underclass celebrating the night’s pickings?) It made no mention of the gun crime, the stabbings, the drugs or the desperate, crazed £5 whores.

What is especially depressing about this whole depressing story, which took place in a depressed area full of depressed people doing depressing things, is that I imagine Stevens himself knew a thing or two about deprivation; and that what he knew would put his assailants’ poxy little gripes to shame. Originally from Kinshasa, which is a horrible city in a grim country, I don’t expect the offer of a place at Cambridge exactly fell into his lap. “I believed in myself and got what I wanted,” he once told his college newsletter.

There are unsettling moments when I feel myself turning into a rabid old-school Tory, and this is one of them. What’s with the pathetic, weedy nonsense from Scotland Yard about hurting yobs’ feelings, when stories such as Stevens’s have, shamefully, become commonplace? Who cares about their feelings? I don’t. I couldn’t care less. I don’t care how hard their lives are: I don’t expect Stevens’s life in Kinshasa was much of a picnic either but at least he was doing his best to better himself to make a new life for his family. And I am so tired of the stupid liberal notion (held by me for decades) that gangs of hoodies are all gigantically deprived and thus need our pity, love and support, rather than our approbation. What they need, actually, is to be locked up.

Deprivation is relative: none of them is starving, all of them are clothed and all of them have access to free education. Besides, one of the yobs arrested in connection with Stevens’s murder is, if you please, the son of a social worker for Hackney council, which doesn’t quite constitute the frontline of ghettohood.

The gangs that periodically terrorise my new extremely salubrious, picture-postcard corner of north London aren’t “deprived” in any material sense that I can understand, either — not when they are wearing several hundred pounds’ worth of designer clothing. They are certainly emotionally deprived to which the only solution, short of eugenics, is first-rate education — starting with nursery and, in some cases, psychotherapy from the age of five.

That is a political point. The broader social point is that the killing in Hackney is the merest tip of a deformed, monstrous iceberg. We are all, wherever we live, at the mercy of marauding gangs of underclass yobs, intent on damage, and there seems to be little that anyone can do about it (which is why I’m sounding so cross. I’d have been less cross 10 years ago, and hardly cross at all 20 years ago, but the crossness escalates with every year that passes because the problem gets worse and nothing happens).

I was recently told by a representative from my local Safer Neighbourhood Team that its powers were somewhat limited: it could ask gangs of boys what they were doing lurking in residential areas at 2am, but since it was not legally allowed to make physical contact with them, it could not actually remove them if vocal persuasion failed.

Besides, the representative said mournfully, they’re often on bikes, which means they move too fast. As for Asbos: not terribly helpful when in some circles an Asbo is a badge of honour. I mean, really: someone’s having a laugh and it’s not you or me.

Being frightened in the street and even in our own homes — feeling scared to intervene when yobs are behaving badly for fear of one’s own safety — has become the norm in this country. We moan about it in the same way that we moan about leaves on the line or automated telephone systems: it’s just everyday life.

You have to gird your loins before opening the local newspaper, because its tally of crimes makes you come over all agoraphobic. I used to be absolutely appalled by gated communities — the super-rich making themselves safe because they can afford to. These days I grudgingly see the point. And that feels profoundly demoralising.

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