‘Why don’t we do it in the road?” That was the question posed by the Beatles in 1968 in the song of that name. The expected answer, quite clearly, was: “Why not?” That year, 1968, was the dizziest moment of the era of letting everything hang out, so to speak. Doing it on the road was really the least one could contribute to the cause of liberation and universal love.

It wasn’t the aggressive John but the nicey nicey Paul who wrote the song. It seems that while with the Maharishi Mahesh Yogi in India, he had seen two monkeys doing it in the road and thought what a good idea it was in all its natural simplicity.

“A male,” McCartney said later, “just hopped on the back of this female and gave her one, as they say in the vernacular. Within two or three seconds he hopped off again and looked around as if to say, ‘It wasn’t me’, and she looked around as if there’d been some mild disturbance . . . And I thought . . . that’s how simple the act of procreation is . . . We have horrendous problems with it and yet animals don’t.”

As a model for human sexual relations, I think there are a couple of things wrong with this vision, whether in the road or not. However, this song was hugely influential; you could almost cite 1968 as the end of sexual modesty in public. It might be unfair to hold the Beatles entirely responsible – there were plenty of much sexier bands. But this song did coincide with and express the beginning of a time of astonishingly flamboyant sexual exhibitionism. In answer to McCartney’s siren call, countless people have taken to doing it wherever they fancy and insisting on their human right to do so. Even tiny children dance to pop music, to adult encouragement, with all the bump and grind of a slaggy old stripper.

Now, 40 years on, we have a couple of well-to-do British expatriates in Dubai shamelessly and drunkenly doing it on the beach. Thou hast conquered, / O pale Liverpudlian. Last week Michelle Palmer, 36, from Rutland, and Vince Acors, 34, of Bromley, southeast London, were sentenced to three months in prison in Dubai for having sex outside marriage on a public beach and offending public decency. They were also fined about £200 and will be deported when they have served their sentences. They were lucky: their punishment could have been much worse.

I have absolutely no sympathy for them but I do think that given the permissive culture of the country in which they grew up – they were born only a few years after 1968 – it is understandable, if depressing, that they themselves didn’t see much wrong with their behaviour.

From their perspective it is apparently quite normal for two strangers to meet at a hotel brunch, drink themselves silly and proceed to perform sex acts on each other in public. It is normal to insult a policeman who has the effrontery to caution them, regardless of the law, and to carry on. That is what Britons do at home and abroad. They belch, vomit, copulate, litter and barge their way through public spaces, dressed like hookers and louts, defying the police without shame or modesty. British expatriates are some of the worst: overpaid, oversexed and all over the place.

Palmer and Acors are appealing against their convictions. Yet by Palmer’s own admission, she was drunk and they were kissing and cuddling. “We didn’t have sex together,” she insisted. “I was lying on top of him.” This is rather to miss the point.

No one cares much whether DNA evidence proves that there was no exchange of bodily fluids. What went on was an affront to the standards and laws of Dubai, which all expatriates are well aware of. If you don’t like the law or the culture of another country, you should stay away. If you go there anyway, you should keep your views to yourself and when in Rome behave as the Romans.

That is not only common sense and a way of staying out of nasty foreign jails. It is more importantly an ancient moral obligation, which all healthy cultures have observed. As a guest, you must respect your host and his feelings. Everyone knows that Muslim cultures believe strongly in modesty and privacy; it is simply rude to go about half-naked or drunk and snogging and shagging in public in an Islamic country, an insult to the host culture as well as a disgrace to our own. I can’t help secretly sympathising with the senior prosecutor in Dubai who said he wished the couple had been given a longer sentence.

Is it surprising that so many Muslims around the world despise us for our decadence when we express our sympathy with British men and women who behave like this? There is something clearly despicable in the permissiveness and hyper-sexualisation of western culture; the result is broken families, unwanted children, sexual diseases and a state of agitation which drives the young into chaos and crime.

This might seem a long way from a fumble on a beach and certainly I would agree that many Muslim cultures take their modesty to extremes of repression. But the connection is there and Muslims, including British Muslims, are right to make it.

PC Plod in this country, however, does not make it. Last week a senior officer recommended that the police should turn a blind eye to sex in public, to avoid offending or distressing people seen doing so, and to protect the human rights of those who frequent open spaces to have sex, particularly those in pursuit of dogging and cottaging, who might easily be alienated or humiliated. His advice is contained in 21 pages of guidance on policing sex in public.

This is the kind of attitude that gives freedom a dirty name. No wonder so many Muslims here look down on the host culture and try to isolate their sons and daughters from its unthinking libertinism.

If we expect ethnic minorities here to respect the host culture, we should make sure it is worthy of respect. If we expect them to behave according to our standards (such as they are) when they are here, so should all British citizens respect their standards when over there.

The careless cultural imperialism of British expatriates abroad – their selfish, insensitive, sluttish behaviour – must be partly to blame for the cultural hostility and separatism that are growing among Muslim minorities at home here today. That is one good reason, among many, for not doing it in the road, either home or away.

minette.marrin@sunday-times.co.uk

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