Figures show that for pubs and wine bars in particular, the military action in Afghanistan has proved a lucrative stimulus. Takings for some of the bigger chains increased by up to 7 per cent in the last three months compared with the same period last year and some retailers say that business is brisker than at any time in 2001. Tobacco manufacturers and bookies, too, find themselves riding an unexpected wave of prosperity.

It is curious that in a time of national gloom, and with global recession snapping at our heels, we react by lifting our skirts and running headlong into hedonism. (In America lipstick sales have shot up by 500 per cent and Weight Watchers has reported significant weight gains among its members.) Surely the obvious response in these circumstances would be to do precisely the opposite — shunning excess as the bodies pile up in Afghanistan? But the facts point to a different story — one which tells us much about human reaction to crisis and mortality. Research shows that despite our worries, we are planning to spend the highest amount ever on Christmas this year — an average of £601 each compared with £589 last year.

We are also having more sex. Condom sales have risen since September as we follow America’s lead by indulging in “terror sex”, which, experts have warned, could result in a small baby boom next summer.

Dr David Weeks, a consultant clinical neuropsychologist at Royal Edinburgh Hospital, attributes this to the fact that during times of stress “we experience a live-for-today feeling and want to capitalise on what’s great about life”.

In the Slug and Lettuce on Fulham Broadway there is standing room only as Robbie Williams thunders from the loudspeakers. Matthew, 26, and his friend Anthony, 21, are doing their own bit for the economy by downing as many pints of lager as possible before last orders. They are construction workers and have given no thought to modifying their behaviour in the current climate. “If we learn anything from what happened it should be that you must live for the moment because tomorrow you could be toast,” Matthew says, snapping his fingers to indicate a sudden death.

Anthony agrees: “My Dad keeps telling me that if this had been a full-on war 100 years ago, I would have been called up to fight and I should thank my lucky stars. I’ll drink to that.”

Mark Hastings, from the British Beer and Pub Association, confirms that trade is flourishing countrywide. The only bars and restaurants not doing so well seem to be those in Central London, which has suffered a huge decline in tourism.

“Trade generally has held up very well,” he says. “Much better than earlier in the year when the foot-and-mouth epidemic was hitting us for six. The industry was losing £35 million a month then, but now things are good. Because there is some uncertainty about the economy people are tending not to go to restaurants at the top end of the market; they are going to bars to eat and drink because it’s better value.”

There is also another factor at play, Hastings says. “Since the initial shock of September 11 there has been a continuous bombardment in the news of heavy stories and that has driven people to want to go out and get away from it.” And if they do watch the news, many prefer to do it in company, huddled around the pub’s TV screens.

Jim Clarke, a financial director for JD Wetherspoon, which has 550 UK pubs, says that turnover increased by 4.5 per cent in September and by 7 per cent in October compared with the same months in 2000. “In the two days after September 11 there was a dramatic fall in custom, but it picked up and has kept going.”

There is a similar buoyancy with cigarette sales, but the reasons for this may be more complex. According to a US survey, a third of smokers say they have bought more cigarettes since September 11 and 5 per cent of former smokers have started smoking again. The survey of 2,018 adults by the American Cancer Society and GlaxoSmithKline concludes that the terrorist attacks “caused many people to retreat to unhealthy behaviour”.

British tobacco retailers say it is too early to collect hard data, but anecdotal evidence suggests that tobacco sales have also surged here in recent months. A spokesman for Gallagher, the country’s second biggest tobacco retailer, says that increases may be due in part to heightened anxiety, but there could be another cause. Since September 11, there has been tighter security at our ports and thus fewer smuggled cigarettes entering the country to be sold on the black market. If more smokers are being forced to buy from legitimate outlets, recorded sales will rise. Some 85 per cent of hand-rolled tobacco and 15 per cent of packaged cigarettes in Britain are smuggled.

Britain’s 12 million smokers smoke 60 billion cigarettes a year, creating a £12 billion market. But if existing smokers had just one extra cigarette each a day that would equate to 4 billion more single cigarettes — or 20 million packets — sold a year.

Liz Buckingham, of Imperial Tobacco, is more cautious and prefers to say that the decline in smoking has slowed in recent months. There are three factors — improved security at customs, the fact that foot-and-mouth had resulted in fewer people travelling abroad and thus less smuggling, and the low duty increase on tobacco in the March Budget. “The market is still in gradual decline, but the rate of that decline is slowing,” she says.

Yet if we are drinking, smoking and betting more we are only following normal human behaviour patterns for wartime. During and after the Second World War smoking quadrupled and the drinking of alcohol doubled, despite the shortages.

During the First World War, the Defence of the Realm Act was passed when it was considered that heavy drinking was endangering the war effort. Fights at the Gretna Green munitions works were so bad that pubs in Carlisle were nationalised and people were banned from buying rounds of drinks to prevent them consuming the lot themselves. Drinking was not the only type of indulgent behaviour. The Second World War saw pre- and postwar booms in marriages and, during 1946-50, a quadrupling of divorces compared with the previous five-year period.

Traditionally, gambling has been shown to flourish during both recession and wartime and so it is proving today. Russell Hoyle, the chief executive of Leisure Link, the biggest provider of fruit machines to British pubs, arcades and retail outlets, is so intrigued by the sudden upturn that he is currently conducting research into the reasons behind it. Income from fruit machines had risen by more than 10 per cent since September. “There almost seems to be a feelgood factor around, which is quite peculiar,” he says. “It’s almost as if people are saying ‘There hasn’t been World War Three after all, so let’s enjoy ourselves’.”

Graham Sharpe, of the bookies William Hill, says the indications are that turnover has increased by up to 30 per cent — but that was also fuelled by the abolition of betting tax in October. “In times of recession, pubs and bookies flourish and the (abolition of) betting tax has coincided with a period when that has been on people’s minds,” he says.

“It seems to be the case that people will keep their little bit of enjoyment even in times of hardship. The attitude is that if you are down to your last tenner you might as well use a couple of quid of it to see if you can win a bit more.”

This does indeed seem to be the case. Dr Derek Lee, a psychologist for Bedfordshire and Luton Community Trust, says people don’t always behave rationally in times of crisis. “What we are seeing is a mass post traumatic reaction,” he says. “September 11 has brought into focus for people that their lives can end at any moment. Smoking and drinking are ways of coping. One of the features of gambling is that it can take your mind off your worries because it’s something that you are totally focused upon.”

These are common emotional reactions to disaster, he says. “It is said that after an air crash, the takings at airport bars increase significantly.” Rather than celebrating the fact that they are alive and taking good care of themselves, survivors of disasters often do the opposite by taking drugs or drinking to excess.

Dai Williams, a chartered occupational psychologist, says that our increased drinking and smoking can be seen as “self medication” against rising levels of anxiety caused by stress and change. “Gambling indicates increasing fatalism and a sense of powerlessness as we feel we are losing control in an unstable environment,” he says.

Meanwhile, we continue to drown our sorrows with enthusiasm. Bob Cartwright, of the Six Continents group which owns All Bar One, O Neill’s, Edward’s and Harvester pubs, says trade is extremely healthy. “It’s not the case in Central London, because the American tourists are staying away, but reports from regional pubs say sales have risen by about 10 per cent,” he says.

Allied Domecq, the world’s second largest wines and spirits group, says off-licences are benefiting even more than pubs. “This is certainly the case in America,” says a spokesman. “People are buying more from off-licences because it saves money and they feel safer being at home right now. But they are still drinking.”

It is closing time at the Slug and Lettuce, but the revellers streaming out are in no mood for going home. “We’re going to find a club,” says Anna, skilfully hiding her Bacardi Breezer under her fake fur coat. “I’ve stopped watching the war on TV and I’m not going to worry about the recession. There’s nothing I can do about it so I’m going to enjoy myself while I can.”

Indeed, as The Book of Isaiah tells us: “. . . and behold, joy and gladness, slaying oxen and killing sheep, eating flesh and drinking wine. Let us eat and drink, for tomorrow we shall die.”