The Government stresses that nothing has been decided for sure and, between now and the publication of the Integrated Transport White Paper in May anything is possible, but the hints are clear. When a politician says, "read my lips, no more taxes," he is almost certainly lying. When he says, "read my lips, there may be more taxes," as John Prescott has been informing drivers since the autumn, it is very probable that he is telling the truth.
The environmental case for hammering the motorist sounds water-tight. Carbon dioxide, which is produced when you burn any fossil fuel such as gasoline, is relatively transparent to solar radiation, yet relatively opaque to the infra-red heat beamed back into space from the warmed surface of the Earth. Ergo, less heat gets out than gets in. The ice melts, the oceans expand and it's goodbye to the Maldives and Holland. By 2020, as we have read, there will be vineyards in Yorkshire. This is just as well, because Burgundy and Bordeaux will be desert by then; or was that going to happen by 2050? Or 2100? The doom-merchants are often vague. Whenever, it is bad, and the motorists are to blame.
Or are they? Statistics muddy the picture: according to the UN (and Friends of the Earth), automobiles account for some 17 per cent of the United Kingdom's estimated 580 million tonnes of anthropogenic, or man-made, annual carbon dioxide emissions (the Government disputes this, insisting the figure is a fatter and rounder 20 per cent). If Labour's plans are successful, we may be persuaded to use our cars a quarter less? Or half as much? What does that amount to in terms of C02? Possibly a fall of 5 per cent, though something between 3 or 4 per cent reduction is more probable. Though the most likely outcome is no reduction at all. As any smoker or alcoholic will tell you, whatever it costs (you may not have noticed in these metric days, but petrol broke the pounds 3 barrier some time ago), and in the absence of a viable alternative, the motorist will continue to pay for the pleasure.
The stated rationale behind higher motoring taxes is to stop global warming. But this is based on a fallacy, because the greenhouse effect is not a certainty. Many scientists are agreed that fossil-fuel burning will cause climatic change of apocalyptic proportions. Many others are not so sure. Reports of the greenhouse effect are usually illustrated by anecdotal and metropolitan evidence: a sweltering London summer, "record" storms on the English south coast and so on. There is evidence that Earth's climate is not inherently stable; thousands of years ago, before the last ice age, the temperatures fluctuated by several degrees in decades, without a gas-guzzler in sight. Global warming may be happening, but it may not be our fault. Maybe the greenhouse effect is just the latest doomsday cult. Remember the population explosion predicted in the early Seventies that was going to leave us all with a square foot of space to stand on? We now believe the population is set to stabilise sometime in the middle of the next century.
However, if the greenhouse pessimists are right, things will be pretty grim, so it is probably better to be on the safe side (that was what the Kyoto summit last December was all about), but do remember to turn on the bullshit detector whenever a minister talks about science. After all, this is a government that banned a substance (beef-on-the-bone) which, by its own admission, stands a one-in-20-million chance of killing you.
If the Government was genuinely interested in the environment, rather than in revenue, it would go after the real polluters. The trucks, the belching elderly taxis, and Britain's bus fleet, powered largely by huge, primitive and badly tuned engines that belch smoke like a Victorian steelworks. At a stroke, the Chancellor could abolish diesel - the filthiest auto fuel (as Parisians found out to their cost last summer when France's peculiar and ill-advised love affair with diesel caused a smog which made life intolerable in the capital). A tenner on a gallon of diesel should do the trick. The road haulage firms would squeal. In New York City, the authorities recently paid for a third of the bus fleet to be converted from diesel to liquefied petroleum gas. Friends of the Earth calls for the conversion of the entire, stinking, London Routemaster fleet to gas; don't bet on it.
Taxing parking and restricting the number of spaces available could make traffic worse, not better. At any one time, some 15 per cent of the cars driving round central London are looking for somewhere to park, and it is slow-moving congested city traffic that causes the most pollution. In many US cities, there are strict restrictions on the hours delivery vans are allowed to load and unload. Few such restrictions apply in the UK, so busy high streets are clogged for hours as the Transits and Bedfords double park, possessing a magical immunity from traffic wardens. One- man buses, one of the scourges of modern life, cause endless delays. And industry and the power generators - the biggest C02 producers - could be brought to heel. Yet there is little to suggest that Labour is ready to take on these commercial interests.
The Government is enthusiastically committed to increasing patrol duties by 6 per cent over and above the rate of inflation in the coming years (we do have to meet our Kyoto targets to reduce C02 emissions to 8 per cent below their l990 levels by 2010). Last week I asked Gavin Strang, the transport minister and scientist, how this money would be used to provide an alternative to using our cars. He said the Government needed to "develop one or more dedicated income streams to fund public transport" - in other words, ring-fencing revenue raised by local authority parking taxation or road charging to fund better public transport. He also accepted that it was "unacceptable" to increase fuel taxes indefinitely, as this would hurt the poor more than the rich: "Sometimes there is a conflict between our social objectives and our environmental objectives," he admitted.
Mr Strang talked about partnerships between the private and public sectors, encouragement for car firms to produce better engines, and he strongly denied that Labour was in any way anti-car. But Mr Strang's worthy and sensible vision of a public transport renaissance won't happen, at least not while an iron chancellor of the exchequer remains at his post. For a start, the Treasury is dead-set against any ring-fencing of parking and other taxes - "hypothecation", it is called - to be invested in public transport. And the Treasury calls the shots.
An integrated transport policy that relies solely on forcing motorists out of their cars without providing them with a reliable, safe and efficient alternative is a sham. The Government is using scientifically dubious, environmental worst-case scenarios to justify a tax hike that it could never get away with if it was targeted at incomes, food or consumer goods. Real measures to combat pollution - tackling the power generators, heavy industry and the commercial vehicle sector - are seen as political suicide, so the poor punter in his car will have to do.
Petrol tax rises are essentially regressive. The people most likely to be forced out of their cars and on to the shambolic public transport network by the "stick-and-stick" approach of dearer petrol, less free parking and road pricing are the poor and unemployed, the single mothers who need a car to visit the supermarket. The list lengthens: the elderly and rural folk, people on low incomes struggling to pay tax, insurance and yet more tax on their jalopies, the disabled and people with large families.
As for the rest of us? Well, we can take a taxi.