BEING a minister is not all fun. Few envied Alistair Darling as he balanced fiercely opposed and sequally legitimate lobbies for and against new airports and runways. The Transport Secretary cannot avoid giving an opinion because any such basic increase in capacity requires large-scale compulsory purchase, because key planning decisions always come back to Whitehall, because this Government wants an “integrated” transport policy and because the timescale for investment is long.

There is another reason. Unless Whitehall gives orders, it is assumed, local people would never allow these facilities to be built.

This week’s aviation White Paper was surprisingly well received, except by those who see their home villages being bulldozed, historic houses and monuments demolished and ancient woods ruined. It vetoed three new airports, backed extra runways for three existing airports, including a key one at Birmingham, and gave ambiguous or conditional approval to three more.

The most controversial decision, however, was the one Mr Darling fudged. The airline industry and BAA, which owns the three biggest South East airports, all want a third runway at Heathrow.

Demand for the extra runway is manifestly there. Financing would be no problem. This appears to be a thoroughly sound business proposition.

British Airways uses Heathrow as its hub and can control costs best if its expansion is concentrated there. Virgin Atlantic and the main US and Continental airlines want to expand at this unpleasant complex because it has by far the most local and long-haul connections. It also still has the largest catchment area of the South East airports, which, together with others not owned by BAA, account for three quarters of UK traffic.

The White Paper says that no other airport is likely to provide this dimension; there is no straight alternative. To the extent that ministers are concerned about maintaining London’s global role in finance and big business, the economic need is met only by Heathrow.

Mr Darling concluded, however, that Heathrow might get a third runway in 15 years’ time but only if pollution levels could be reduced. The airline industry thinks it has got its runway. Hundreds of thousands of people living in historic, wealthy areas of incalculable environmental value, who already suffer from an endless succession of landings, have been given some hope.

In reality, the decision has simply been put off until after at least one election, for some future Secretary of State. In exchange, Mr Darling backs a second runway at Stansted in Essex, in a semi-rural area where fewer people suffer albeit they suffer more.

Use of Stansted has grown amazingly fast in the past few years, but only because it has become the chief base for Ryanair and holiday specialists and has hosted the low-cost airline explosion. Even so, there is room for 50 per cent growth in traffic without congestion. That growth is also the most problematical.

Low-cost airlines are now focusing on expansion across the Channel, mainly because vested interests have managed to keep them out until now but partly because the UK market cannot deliver such rapid growth for long. Traffic is also more price-sensitive. Ryanair’s battle with the French authorities has revealed, for instance, that some routes are only viable if subsidised by the airport of destination.

Campaigners worried about global warming are also asking ever harder questions about the privileged tax position of aviation fuel. Although flying accounts for a modest share of greenhouse gas emissions, they are claimed to be disproportionately damaging.

Fuel is tax-free because it would be impractical for only some countries to tax it. Americans, who use air flight the most, would not join in. Even if tax were applied across the EU, European airlines would be put at a disadvantage.

Alternatives to an aviation fuel tax are, however, almost certain to find favour with finance ministers. Higher landing taxes, levies related to fuel efficiency and EU-wide emissions trading are all likely to add to airline costs.

For all these reasons, building a second runway for Stansted is a much less convincing business prospect. BAA has welcomed the plan, but only if it can raise charges at its other airports to help finance the investment. Airlines using Heathrow are already trying to persuade the Civil Aviation Authority to ban BAA from subsidising Stansted by charges at Heathrow and Gatwick.

We shall never get the best economic decisions on infrastructure if Whitehall decides everything. Ministers have to give an opinion, but that should not be the last word. Imposing decisions that have no basis in market forces or democratic voting has itself created the phenomenon now decried by centralists as Nimbyism.

People now know that unless they manage to stop potentially damaging development before it starts, they will be regarded by ministers as a soft touch and be landed not just with second runways but also industrial parks, high-rise clusters and nuclear waste dumps.

For developments to be economically justified, winners should be able to compensate losers enough for them to vote for the development and still leave a surplus. When solutions are imposed with minimal compensation, we hear only the passionate opponents and not those, who may or may not be a majority, who agree moderately.

Motorway building came to a halt after the disgraceful destruction of Twyford Down because Whitehall had used central power to force a road through on the cheap. The cost of scrimping was high.

Only Heathrow, among the nation’s airports, could remotely be regarded as of national strategic importance. In every other case, airport economics could be tested by local voting. If people knew they had a choice, they would more likely plump for more regional airports of a size they could control than veto them all.

graham.searjeant@thetimes.co.uk

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