The scuffles that broke out yesterday between police and protestors in the vicinity of Heathrow airport had been on the cards since this particular climate-change demonstration was first mooted. From the initial - failed - effort of the British Airports Authority to slap an injunction on more than 15 protest groups to yesterday's show of strength by police, a sense of confrontation was in the air.

Of course, we understand the authorities' concerns about the strategic nature of Britain's busiest airport. And we appreciate the Government's worries about security in general and airport security in particular. Still, it is hard not to see the level of the police presence, their very obvious, some might say provocative, visibility, and the equipment that suggested preparation for a full-scale riot as out of proportion to any threat. For all that, this was an overwhelmingly peaceful protest, in practice as in conception.

And its purpose, as stated by the organisers, was modest: to start a debate about airport-linked damage to the environment. As such, it can claim to have been a success. Some 1,500 people gave up a week of their lives to take part in the protest camp, which was entirely peaceful. They held workshops and, despite the best efforts of several powerful lobbies intent on preserving their special interests, they made their arguments heard. What was also clear was that they received a largely sympathetic hearing, even from those with a direct personal interest in the continued functioning of the airport, such as employees, passengers and even pilots.

Heathrow epitomises pretty much everything that is wrong with the aviation sector: its gargantuan appetite for space; its insistence that the world cannot function properly without it, and its association with some of the less attractive aspects of big business - such as a dog-in-the-manger attitude to landing slots. Complaints about its poor functioning during the early summer were met with circular arguments about the need for new terminals and new runways - Heathrow will not be more passenger-friendly, we were told, until terminal Five is up and running, and then not without another runway.

These are arguments that are predicated on an ever-increasing demand for flying. Not only is this by no means proven, but there are ways - some of them quite simple - in which flying could be curbed and, when there is no choice but to fly, made less damaging to the environment. As a paper, we support an EU-wide tax on aviation fuel and believe that the cost of flying could be much higher than it currently is without impinging on individuals' freedom. The price of flying should be made to reflect the real cost to the global environment.

Aviation at present accounts for 7 per cent of Britain's carbon emissions. But by 2050, it is estimated that emissions from this one source could exceed the whole of Britain's current emissions. More efficient aircraft may temper that projection, but the Government also needs to take action by fostering development of the rail network and encouraging alternatives to flying. It could also scotch the idea, still prevalent, that economic growth depends on increased air traffic.

While this protest was principally about climate change, it was not only about carbon emissions. It was about the villages and landscape that will be blighted if airport expansion continues, about the many more people whose peace will be destroyed by aircraft noise and about the practical counter-measures that can be taken. The many vested interests associated with flying should not be allowed to use a small number of skirmishes to obscure the message the campaigners set out to convey.