A year ago, as a dreadful dust cloud hung over Lower Manhattan and the world recoiled in horror at the images of hijacked passenger planes crashing into the Twin Towers, many predicted the world had been changed forever.
The terrible events of September 11 would have a lasting impact on every aspect of life - including the messages created by the marketing and media industries.
On the first anniversary of the attacks, we look at whether those predictions have come true - and whether September 11 really has changed the way we live and do business.
The airline industry was facing a major downturn even before the attacks created a crisis of confidence that airlines were powerless to change. People simply didn't want to fly.
Bookings fell 50% after the attacks, the industry lost £7bn last year and shed more than 120,000 jobs. The two US carriers whose planes were hijacked in the attack, American Airlines and United Airlines, continue to struggle with the economic aftermath of the attacks. Last month AA axed a further 7000 staff and it has cut around 9% of flights. US Airlines, which has lost about £2.6bn so far this year, became the first US carrier to file for Chapter 11 bankruptcy.
The picture for European long-haul carriers has been equally grim. Swiss Air and Sabena have gone bust, while Virgin Airlines last month revealed it had taken a hit of £100m to cover the impact of the terrorist attacks - and recorded a pre-tax loss of £92m. British Airways has axed 13,000 jobs since the attack and cut routes.
Passenger numbers between Europe and the US remain down by around 13%.
The airline business has also struggled with its marketing. Most US airlines stayed off television for months after September 11.
Today airline advertising focuses on price, rather than the pleasure of the flying experience.
BA's only major television campaign has been aimed at the business market.
Martin George, BA's marketing chief, says: "We've had to go right back to the beginning - persuading people it's safe to fly." Both BA and Virgin have pulled all advertising around the anniversary date, as have many US airlines. Yet European budget airline brands such as easyJet and Ryanair have continued to thrive - their flights are cheap and short - and in the current climate, that's exactly what passengers want.
One year on, the major changes in consumer attitude are fairly predictable. US consumers are now more wary of foreign travel, with 39% saying they are less likely to travel abroad, according to Euro RSCG Worldwide's Mind and Mood Monitor. They regard 'home as a haven'.
Sixty-eight per cent of US consumers say they admire the US more than before and there is far greater respect for fire fighters and the police.
US consumers are still shopping. Their propensity to buy US-made goods has grown stronger - 50% of people aged over 50 say they are now more likely to 'buy American'. Various pundits have predicted that because of September 11, consumers would become more hedonistic or more stay-at-home. But for the most part, consumers are behaving as they did before September 11. And that in itself is a victory over terrorism.
For many months after September 11 the insurance industry said it would be the sector hardest hit by the attacks.
The World Trade Center housed some of the world's leading financial companies, and many of the dead worked in the sector.
As well as the emotional toll, it took a massive financial toll. The total bill is still being worked out, but is expected to be as high as £13bn.
The result has been spiralling insurance costs - to the point where some companies are now complaining that the cost of insurance threatens to put them out of business.
Last month it was revealed that the British government is to hold talks with the country's insurance industry to tackle the problem of small firms finding they cannot afford to insure their staff.
The US has gone from being a country where there was only limited cover by businesses for acts of terrorism on US soil, to one in which most large firms now have terrorism included in their cover.
Earlier this year, New York embarked on a major drive to protect its tourism business. The city launched a £24m advertising campaign urging people to 'Come See New York in its Finest Hour'. But the most recent figures show that NYC visitor numbers dropped 14.3% last year, with around 5.4 million fewer people visiting the city after September 11 compared with 2000.
Visitor numbers to the UK, whose tourism industry was just beginning to recover from the effects of the foot-and-mouth outbreak when the attacks took place, fell by 9% to 22.8 million and spending by tourists dropped 12% to £11.3bn. US visitor numbers dropped 17% in September last year, 30% in October, 23% in November and 7% in December.
In the first six months of 2002, US visitor numbers were down 11% compared with the first six months of 2000, the last 'normal' year for the industry.
Marketing support came in January with a £5m campaign through Abbott Mead Vickers BBDO declaring UKOK. The message, designed to reassure overseas visitors - particularly Americans - that the UK was a safe place to visit, received a lukewarm response from both tourists and the industry itself.
In May it was replaced with a £40m campaign through BMP DDB, with funding split equally between the government and the private sector. The campaign focused on the country's heritage and the Queen's Golden Jubilee.
US TV networks cleared their schedules of ads as the horror unfolded on TV screens. Major networks CBS, ABC, NBC and Fox were commercial-free zones for four days. The usual diet of ads for cars, Coca-Cola and Budweiser were deemed inappropriate by both the networks and the advertisers themselves.
Total lost revenues for commercial TV as a result of dropping ads during the week of the attack was £241m. Total ad revenue lost over the months that followed is thought to exceed £319m.
The US film and TV industry promised to take a hard look at the kind of material it was producing. Warner Bros shelved a movie called Collateral Damage in which Arnold Schwarzenegger plays a fire fighter whose wife is killed in a terrorist attack. Some suggested it might never be shown.
A few months later it was premiered in New York with an invited audience of firemen and women.
"There was a lot of talk about major changes, but I don't really think that's happened," says John Hardie, former marketing director of ITV and now managing director of Disney TV in Europe. "I think we're probably seeing more films for families and kids, but there was a move toward that before September 11."
Financially, the attacks added to an already pressurised media sector.
AOL Time Warner and other media giants have seen their values and ad revenues plunge over the past 12 months, but most of this can be attributed to the economy.
Like the media industry, advertisers looked long and hard at the messages they were producing immediately after the attacks. The wave of patriotism that swept the US after the attacks has lasted longer than sensitivity about images of violence and explosions.
The Ad Council, a not-for-profit organisation funded by the US media and ad industry, has launched a series of ads extolling the virtues of 'freedom and the American way'. It has also run anti-racist campaigns to try to counter anti-Muslim reaction.
Post-September 11, some advertisers tried to wrap themselves in the flag.
A TV ad from General Motors urged viewers to 'keep America rolling' by buying cars with a zero interest-rate deal.
Some advertising patriotism has now moved into nationalism. Last month Ford announced it had signed up country singer Toby Keith, whose controversial song, Courtesy of the Red, White and Blue (The Angry American) has proved a big hit since 9/11. It includes the line 'You'll be sorry that you messed with the US of A, cause we'll put a boot in your ass, it's the American way'. Keith will appear in Ford's radio, TV and press work.
In the UK, Malcolm Earnshaw, director general of the Incorporated Society of British Advertisers, says: "Despite how shocking it was for everyone, it has not had an obvious impact for UK advertisers - other than its effect on the economy."
The world's big three advertising groups, WPP, Omnicom and Interpublic, have all said September 11 had a significant impact on spending, and deepened the cuts being made by marketers to their advertising budgets.
THE EXPERTS' VIEWS
Rita Clifton, chief executive, Interbrand
Many people describe the events of 9/11 as 'the day that changed the world'. But despite the appalling tragedy, there is no real evidence that it was the day that dramatically changed world brands.
While it has had an obvious and specific effect on travel-related brands, the greater evidence is that existing trends in global brands and the practice of global branding have been sharpened.
Overall, global brands increased their contribution to shareholder value from 33% in 2001 to 38% in 2002. Both Coca-Cola and McDonald's - 'classic' global US brands - increased their brand value over that period.
Reduced travel and consumer concern affected the brand values of Disney and American Express.
American brand and corporate culture has historically had a 'do it our way' reputation. But, the evidence of changing attitudes could already be seen in McDonald's' efforts to embrace local customs and cultures - such as vegetarianism in India.
Coca-Cola's marketing activities around the World Cup also show how much it understands global - as opposed to US-dominating - needs these days.
Despite the political rhetoric, recent events have accelerated a greater willingness to listen and adapt by ambitious global brand firms.
At their best, brands have the power and economic clout to change the world in a positive way - and often in a way that transcends political dogma. The onus is on brand owners and influencers to show how that power is used responsibly.
Sir Martin Sorrell, group chief executive, WPP
The most surprising thing is that superficially, at least, it seems that marketing life has continued relatively unaffected. Clearly the events of September 11 had a material impact in the very short term, with the sharp contraction of spending at the end of September and in the final quarter of 2001. September 11 exacerbated recessionary trends that were already in place.
I say superficially because I think the impact of September 11 may have been deeper but less apparently so. First, consumers and therefore advertisers and marketers started to reassess their values: patriotism, religion, family, the home, apple pie and motherhood have become significantly more important and real. The resurgence of these values has been reflected in post-September 11 communications.
Secondly, and perhaps more significantly, September 11 may have led to a more fundamental reassessment of what we do. Advertisers and marketers, after cutting spending after September 11 and finding that life did not end, may have started to examine more fundamentally their advertising and marketing spending habits. They may have started to question more fundamentally the value of such expenditure and the reasons for it.
I do not believe that this is bad news. Ultimately, it may result in our clients reaffirming the added value of what we do. They may well discover that cutting spending, particularly in recessionary times, is a dangerous occupation. Certainly, all historical data and evidence point to this.
Andrew Robertson, president of BBDO North America, based in Manhattan
In the second week of December 2001, New Yorker magazine carried a wonderful cartoon. It showed a couple in bed together, and the woman was talking.
The caption read: 'Look, if you want to have sex, just ask. There is no need to preface everything with the words 'in the light of recent tragic events'.'
For me this represented a critical moment in the return to 'normalcy', as it is called over here. A joke, not about September 11 (which would have been, and frankly always will be, unthinkable), but about the way it was being talked about. Irony, the death of which had been solemnly announced in Vanity Fair immediately after the attack, was back.
The attacks were a shared experience for everybody in this huge country and created a greater need for, and sense of, belonging and community.
The Stars and Stripes that appeared in September are just as visible today, from little flags on aerials and bumper stickers on cars, to those on flagpoles in gardens and those that seem to cover the sides of entire buildings.
But it would be inappropriate to try to wrap yourself in it to sell people things, as General Motors did in the fourth quarter last year with its 'keep America rolling' interest-free finance offer.
September 11 lurks in the background of everything, on the talk shows, at dinner. It is still a story, and still, therefore conditioning, to some extent, the way scripts and ideas are written. But it is not the only story.