On this occasion, the parents were a seemingly educated Californian couple, and I suspect they had learned parenting the way Manuel in Fawlty Towers had learned English - from a book. The father sat like he was on Mount Rushmore, grim-faced but silent and ineffectual. The mother maintained a tone of reasoned sympathy throughout the 45-minute ordeal of wading through the menu for food that would not terrify her children and cajoling them to put some of it, any of it, into their mouths - an outcome fervently wished for by everyone, since it might halt the whines.

"I know you're a little cranky, sweetheart, but you like grilled cheese," she cooed. "And if you eat a little more, then maybe the uptight English woman at the next table will stop gritting her teeth and sighing." Or that's probably what she wanted to say.

Let me clarify: I consider myself a liberal parent. I listen to my children, I value what they say, and try to explain pretty well everything. And I too have an annoying habit of softening every reprimand with "darling", "sweetheart" or "honey". But I firmly believe there is a limit to how much you can expect the world at large to put up with from your kids. When ours get cranky in a restaurant, we explain and coo and cajole, but beyond a certain point we take them outside, away from other diners, and ask them politely to shut the hell up.

We came back from California to find the papers full of feral kid stories. Well, parliament isn't sitting, and the mayoral election hasn't hit its stride yet, so feral adults were harder to find, I suppose. For many middle-class liberals, reading about teenage gang warfare and crime rates among the under-10s gives both a feeling of helplessness and a comforting sense of distance. We can shake our heads and click our tongues, and congratulate ourselves on what a good job we're doing as parents. But there are plenty of, admittedly less extreme, indicators that children from affluent backgrounds are being over-indulged and - yes, let's use a really unfashionable word - spoilt.

An item on Woman's Hour lamented the problem of teenagers being sleep-deprived because their rooms are chock full of tempting technological stimuli. Why would you want to sleep when you could be online, being groomed by some 58-year-old purporting to be a Danish schoolboy? However, the suggestion that perhaps the TV, the computer and Nintendo should be removed from the teenage bedroom was met by a gasp of disbelief. When did we become so tyrannised by our young? In this paper I read that 424,000 pupils had stopped taking school meals since the Jamie Oliver-inspired healthy-eating drive took hold. That means 424,000 sets of parents allowing children to buy a fat-filled takeaway. Only yesterday we learned that only 2.5% of children take enough exercise each week.

I hate to come over all Nancy Reagan, but if we really want to be good parents we have to relearn the word "no". Of course it can be "no, honey", or "no, I'm sorry", and it must always, always be "no, and here's the reason ..." But we have to be bloody, bold and resolute about this. It may be more than one small step from "Can I have a computer in my room?" to "Can I have a gun?"; but if we don't insist on good nutrition and plenty of sleep and unselfish behaviour, if we don't seriously get firm, we too are neglecting our children. Honey.

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