As Socialist Review went to press protesters were due to converge on Heathrow in a demonstration to oppose the airport's expansion.
The groundswell against a third runway demands attention. But other voices have the ears of Gordon Brown's government - the lobbyists for British Airways (BA), airport operator BAA and the bosses' CBI. BA's future profits require expansion if they are to follow the record £875 million operating profit in the year to March.
The Department for Transport signalled the expected go-ahead for expansion a fortnight before the demo, telling MPs it recognised "the immense value of Heathrow as an international hub airport". The campaign to stop it has brought together local people who are angry at the increasing noise and congestion, and those concerned at the wider threat of global warming.
Aviation leaders repeat endlessly that flying accounts for 2 percent of world carbon dioxide emissions and maintain they are victims of an environmental lobby that targets air travel while other industries are more polluting.
Some of this is true. Shipping accounts for 8 percent of world carbon dioxide emissions and road traffic for more than 20 percent in Britain, and there is huge pressure on airlines to cut their use of fuel with oil priced above $120 a barrel. However, aviation is responsible for up to 6 percent of Britain's carbon dioxide emissions so there is reason enough to rein in Heathrow.
Significantly, carbon dioxide is just one of a cocktail of global warming gases produced by flying. At an altitude these magnify atmospheric warming, perhaps by a factor of 2.5. This figure is disputed, but a multiplier effect seems certain.
Just as important, air travel is growing at a rate outstripping every attempt to reduce its emissions. The latest aircraft are increasingly fuel efficient - the Boeing 787 due for launch this year should use 25 percent less fuel than the aircraft it replaces. But airlines are expanding faster than reductions in emissions and have been doing so for decades.
Partly that is because individual aircraft fly for 20 years or more, so the efficiency of the latest model makes little impact on the overall contribution of an ageing worldwide fleet. But crucially air travel expands by an average 5 percent a year, when the annual improvement in fuel efficiency is 1 to 2 percent.
Industry and government gloss over this and stress the economic case for expansion. They argue there is demand for travel - most flights do not take off empty - and if people do not fly from Heathrow they will do so from Amsterdam, Paris or Frankfurt. These airports handle fewer passengers than Heathrow, but are growing fast. They have more runways, less congestion and more routes than Heathrow - so business, profits and jobs will be lost if Heathrow does not grow. The aviation unions broadly agree.
Airlines also add that congestion increases emissions. Aircraft can spend 40 minutes above Heathrow waiting to land. A third runway would cut that. Of course, airline bosses do not expect that to be the outcome - they intend to add flights.
Building the runway might take ten years. In the meantime moving to mixed use of the two existing runways - alternating takeoffs and landings on each throughout the day - could increase traffic by 15 percent.
That would not just increase emissions and pollution from road traffic; it would remove a respite for people under the flight paths. At present the runways are used either for takeoff or landing and switch use in mid-afternoon to give people a break from takeoffs, when aircraft are most noisy.
The government made up its mind long ago, although it has yet to sign off expansion formally. However, the forces ranged against it are growing, as new London mayor Boris Johnson and the Tory London Evening Standard have realised, leading them to question the plans.
In a rational world a majority of us might decide some air travel was desirable and ration it, while scrapping business jets, cutting back on flights and cargo, flying only the least damaging aircraft and investigating alternatives. We might decide we could retain carbon fuel for this reduced air travel until we found something else, or we might conclude the consequences were too grave. Either way the decision would reflect the interests of the majority. Fat chance - for now.