Dominic Lawson: If we tax cars, then why not cattle?

Who knew it would be so easy to save the planet? This is the first paragraph from a disconcertingly encouraging story in yesterday's Independent: "Curry spices could hold the key to reducing the enormous greenhouse gas emissions given off by grazing animals such as sheep, cows and goats, scientists have claimed."

Apparently, researchers at Newcastle University have discovered that coriander and turmeric, when ingested by said grazing animals "can reduce by up to 40 per cent the amount of methane that is produced by bacteria in a sheep's stomach and then emitted into the atmosphere when the animal burps" – as they all do, epically.

How to stop cows burping is the real front line in the greenhouse gas reduction business. Methane is approximately 20 times more powerful as a greenhouse gas than CO2: each day one of Britain's 10 million or so cows pumps out (from its front end, mostly) up to 200 litres of methane – equivalent in its so-called "greenhouse effect" to significantly more than the amount of CO2 produced by a Land Rover Freelander on an average day's drive of 33 miles.

This is where Sir Paul McCartney comes in (and I don't mean driving a Land Rover). At the weekend the ex-Beatle produced an entire Sunday magazine colour supplement devoted to the benefits of vegetarianism; among its many fascinating assertions was that "the UN has calculated that the combined climate change emissions of animals bred for their meat were about 18 per cent of the global total – more than cars, planes and all other forms of transport put together".

If that's the case, why is it that whenever the world's leaders meet to pretend to do something about "saving the planet from climate change", the topic of converting mankind to vegetarianism never comes up? I can think of some reasons. First among them is that if an elected leader in the West were to make such a suggestion to his own people, he would face ridicule, or even electoral annihilation. We love our meat (or at least, the vast majority of us do) and the idea of a government making it much more expensive, let alone banning it, would be seen as a grotesque infringement of a basic freedom – to eat what tastes nice to us.

Lord (Nicholas) Stern is generally accorded a respectful audience when he preaches the need to reduce our use of fossil fuels; yet when, nine months ago, the author of the Stern Review on climate change raised the idea that we should switch to a vegetarian diet, he was greeted with abuse – and has not repeated the suggestion in public since. Yet, objectively, making meat more expensive is no more of an infringement of a fundamental freedom than making travel cost more. In fact, freedom of movement – which is what affordable petrol provides, especially in rural areas – is a more important form of liberty than the right to a meat-rich diet.

More to the point, the eating of meat rather than any alternative diet is neither here nor there as far as the wider economy is concerned: its abandonment would be terminally bad news for livestock farmers, but that's all. Without fuel for transportation, however, not only would the entire country grind to a halt, but people might actually begin to starve.

It is, in this context, inherently odd that petrol is taxed at punitively high levels throughout Europe, while the production of meat is subsidised. Producers of crude oil in the North Sea are taxed at up to 75 per cent on the stuff they bring ashore, and then we, the end users, are taxed a further 70 per cent or so on what we put in our cars. These taxes on energy consumption are set to rise dramatically, as the coalition government seeks to honour its Labour predecessor's proposed "environmental levy" on electricity bills.

Last week the Fuel Poverty Advisory Group said that "fuel poverty" levels had almost quadrupled over the past six years, with nearly five million households so affected. It went on to argue that the bipartisan approach of ever-increasing tax on fuel was "regressive" and having "a disproportionate impact on those on low incomes".

Meanwhile, the same poor, insofar as they pay taxes, will simultaneously be subsidising the EU's grotesque Common Agricultural Policy, which in all costs consumers €55bn a year. Many of those subsidies exist solely to maintain the continent's production of red meat; for example, 38 per cent of the income of Welsh cattle and sheep hill farmers consists of straight subsidy.

This may seem ludicrously paradoxical, but there is an obvious reason, based on psychology rather than economics or science, why governments ferociously tax greenhouse gas emissions from cars, but subsidise those from animals. We like animals; they seem an extension of ourselves – organic, if you like. Cars, however, are alien things, without a heart pumping away just like ours.

This is why car manufacturers have always attempted to market their product by portraying their cold, metallic creations as in some ways human, at least in the sense of being possessed of a personality. At its crudest, this is amplified, at motor shows, by plonking a bikini-clad beauty on the bonnet, to make the thing seem pet-able.

You will have spotted another paradox here. If we like animals so much, why should we want to slaughter and eat them? The vegetarian would argue that this paradox is explained by the fact that those who eat hamburgers rarely bother to discover exactly what happens to animals to turn them into the conveniently shaped product that they consume with their chips. Hence Sir Paul McCartney has delivered himself of the aperçu that "if slaughterhouses had glass walls, everyone would be a vegetarian". Sadly for Sir Paul, I'm not sure that knowing about the entire process would have any such effect. I have contentedly devoured lamb from our own fields, even those my daughters gave cute names.

After all, you will very rarely come across a vegetarian livestock farmer. They would doubtless point out that – quite apart from the other uses of their herds, such as grazing hillsides and supplying wool and leather – if we were logical in our concern about the anti-environmental emissions of livestock, we would wipe them all out, rather than just choose not to eat their flesh.

For example, Paul McCartney keeps countless sheep on his Sussex farm, which all live to a ripe age, burping and farting away into the animal equivalent of senility. Good luck to Sir Paul, I say, given that his hundreds of millions from song-writing enable him to keep his herds as pets rather than as produce; but if he really wants to reduce his estate's methane emissions, he would slaughter the lot of them.

The question remains, however: why do the great majority of those campaigning against what they call "man-made climate change" not argue that we all become vegetarians?

I'll hazard a guess. You can imagine a modern, highly industrialised economy devoid of meat-eating; but you can't have such a society without readily affordable fuel – which means coal, oil and gas. Yet it's exactly that prosperous consumer-driven way of life that the green movement wants to dismantle. Arguments about climate change are merely a means to that end.

For this reason, I doubt the green movement will be very happy about Newcastle University's breakthrough of feeding ruminants with curry spices: deep in its puritanical heart is a distrust of anything which might solve "climate change" without making us suffer.

d.lawson@independent.co.uk