A friend who lives in the country recently held a big 21st birthday party for her daughter. “Where did you put everyone up?” I asked. “Did you billet them with people near by?” Her daughter looked shocked. “No, they all camped. Otherwise they would have had to drive back after drinking.”

None of her university friends would dream of driving drunk, she claims. What a change in a generation! I’m not proud to admit that I often drove drunk when I was a student, and so did all my friends. Nobody really disapproved: the only danger, we thought, lay in being caught.

Then came Peter Bottomley, a Minister for Transport in the 1980s, who set out on a mission to change attitudes to drunken driving. Much to my surprise, it turned out to be a great success. Twenty years on, there are still a few diehard drivers — mainly middle-aged alcoholics — who won’t break the habit. But now most of us are a lot more careful, and would be horrified if an inebriated guest tried to drive home.

In the past few years there has been a similarly dramatic change of attitude towards the environment. This week, we heard that sales of 4x4s had fallen in Britain for the first time. Sure, petrol has become a lot more expensive and politicians are threatening to whack punitive taxes on the Chelsea tractors. But also, what used to be thought of as enviable motors have now become embarrassing. As Ken Hurst, of The Manufacturer magazine, who monitors the figures, puts it: “Possibly children who once saw the vehicles as status symbols, now feel ashamed when they are dropped off at the school gates.”

You would have thought that driving down the Kings Road in a vehicle meant for negotiating rutted tracks would be embarrassing enough. But that’s not the issue. It’s the petrol they consume and the pollution they emit that have become socially unacceptable.

Just five or ten years ago, only the most environmentally conscious minority cared about such things. They were the ones who bothered to take their empty bottles to the bottle bank while the rest of us chucked them in the bin. Now, though, almost everybody recycles. Throwing an empty beer can into the general rubbish makes me feel distinctly uncomfortable. It never used to. So what has changed? Global warming was happening five years ago. The packaging of our supermarket food was just as wasteful. Our Kenyan snow peas had just as far to travel then. Lots of us knew that we ought to care, but we couldn’t quite bring ourselves to do so.

The difference, I believe, is the new consensus on the issue. And for that, we can, in part, thank David Cameron. While there was still one main political party that did not indulge in greenery, that prided itself on being the motorist’s friend, it was easier for sceptics to believe that they were in one camp, while the environmentalists were in another. They could even deride the idea that climate change was happening at all. If they did so now, they would be laughed to scorn. The few scientists who still refuse to entertain the notion of global warming sound like those apologists for the tobacco companies who insisted for years that smoking did not cause cancer. We have truly reached a tipping point.

People are really starting to wonder now how they can lead a more environmentally friendly life — people who had never questioned the way they lived. They are buying reusable carrier bags, using the car less, spurning supermarkets for street and farmers’ markets, using low-energy lightbulbs.

Some countries are already well ahead of us. Interestingly, even in the US, sales of 4x4s have fallen by 28 per cent in a year. The Dutch, Germans and Scandinavians are horrified when they see our supermarkets spewing out free plastic bags or our households failing to recycle. To them it has become an article of faith. Just as I wouldn’t dream of dropping a Coke can in the street, they wouldn’t dream of dropping it in a non-recyclable rubbish bin. And moral habits, once acquired, are hard to break. Which means that it is unlikely Britain will ever again be as casually environmentally unfriendly as over the past few decades.

Younger people are even more environmentally conscious than their elders. They will bring up their children with precepts that, to an older generation, are still novel. As consumers, they will demand higher standards from the businesses that serve them. I bet, for instance, that excessive packaging will have disappeared from supermarket shelves within a decade or so. And food miles will have shrunk dramatically.

These 21-year-olds will not just avoid drinking and driving. They will avoid polluting too. It is a powerful social revolution, and one that is badly needed by the planet. At last, climate change has led to a sea change — and I’m not talking about the temperature of the ocean.

Painful verité about French healthcare

Isn’t the French health system marvellous? Don’t we all wish the NHS could match it? Well, oui et non. Listen to this story from a girlfriend of mine who has just returned from a holiday in the Cognac region.

She had dropped a piece of heavy furniture on her big toe (don’t ask) and was in agony. After several painkillers and an hour’s application of ice failed to do the trick, she persuaded her host to drive her to the casualty department at the local hospital.

“You’d have done better to put ice in your cognac and drink it,” said the doctor, before warning her: “This is going to hurt.” (Why is it that British doctors and nurses only ever refer to “slight discomfort”?) A high-tech trolley was wheeled in, on which sat — wait for it — a paper clip and a cigarette lighter. The lighter refused to work, so my friend offered the doctor a box of matches. He proceeded to unfold the paper clip and heat up the end with a match. He then used the hot end to burn a hole in her toenail to let out the blood that had built up underneath.

Merveilleux, n'est-ce pas?

Gathering moss

Hosepipe ban? What hosepipe ban?

Our lawn is as green and lush as an Irish meadow in the spring (well, nearly). I was feeling rather smug about it until my husband pointed out that the green stuff was actually moss, not grass. Still who cares? It’s nice and spongy underfoot. Seems like the perfect antidote to drought.

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