Why are David Cameron’s Tories promising to punish the electorate in the cause of greenery? Governments do punishment, oppositions do mood music.

Cameron appears to believe, on the advice of his pollster, that the British people will accept some sacrifice to “save the planet”. But it is one thing to create an ecological comfort zone by hugging a husky, quite another to tell hard-nosed voters that “material gain is making us less happy” and they should be taxed to protect their children and grandchildren from their parents’ improvidence. Cameron is not just taking a risk. He has been at the fruitcake.

Yet the campaign against global warming has been one of the most remarkable political sagas in recent history. Since I was scared witless some years ago by a conference on global cooling (caused by greenhouse gases shielding the earth from the sun), I came to warming with fingers firmly crossed behind my back. Was this another scam from Big Science for more grant, or from BBC producers for another nature blockbuster?

United Nations conferences in Rio de Janeiro in 1992 and Kyoto in 1997 shifted the debate from hippiedom to cosmic diplomacy, but failed to make much impact on policy, whether at home or abroad. Tony Blair and Gordon Brown oversaw 10 years of falling petrol taxes, cheaper motoring, tax breaks for air travel and hypermobility, all to be encouraged by more low-density rural development. They talked the talk but walked in the opposite direction, give or take a few wind-farm subsidies.

In the past two years a rush of statistics has demonstrated not just that warming is an incontrovertible fact but that humanity is almost certainly its chief cause. If the past century’s soaring carbon release was an exercise of economic choice, then surely carbon reduction could be as well.

To this, sceptics objected that, even if it were so, action on climate change was futile since it could not embrace China, India or even America. Why should Europe punish itself when the earth was going to hell in a handcart anyway?

At this point the public has proved unusually philanthropic. While its own experience is that climate has not changed much, it has accepted what it is told by scientists, ecologists, historians, even philosophers. It has appeared to display a genuine sense of collective alarm. Climatic turbulence, desertification and rising sea levels would cause hardship beyond the capacity of states or market forces to respond. James Lovelock’s Gaia can no longer maintain an equilibrium in which normal human life survives.

In his report to the government last year Nicholas Stern, the economist, called global warming “the greatest market failure the world has ever seen”. If carbon emissions are harmful to the earth’s atmosphere, people should try to reduce them and governments should induce them to do so.

In other words in just two years the fringe has become the political mainstream. Corporations find their carbon emissions under scrutiny by ethical investor lobbyists. Fashion pages, car designers, house builders, even travel supplements have caught the green bug. Governments and political parties must satisfy younger supporters clamouring for deeds not words.

Something must be done and we do not mind making our own contribution to it, even if it starts with a recyclable bag.

So far, so feel-good. As yet the British government does not know how to respond beyond setting itself an implausible Blairite target, regularly changed, to reduce carbon emission by x amount in year y, or whatever you like. Brown talks of “the challenge of global warming” but regards it as a challenge that he need not meet.

Having indulged carbon emissions for a decade, can he suddenly penalise them? Will he really tax motorists off the road or tax weekend breaks away from Gatwick and Luton? Will he attack mobility by discouraging the development of green acres rather than brown ones? Will he promote nuclear power when the green lobby has fed so long at CND’s breast as to be in denial over it?

Last week Cameron’s Tories dared to answer these questions, upstaging Brown and the Labour party in the process. An extraordinary 550-page policy document on the environment grandly related human happiness to the present and future state of the planet. It contrived to be both general and particular, leading the Conservatives away from naive free marketeering towards Cameron’s theme of social responsibility. If a green Britain had to be a country ready to wrap up to keep warm, to holiday at home and to work, shop and learn locally, so be it.

The Tories are considering many policies mooted in Rod Eddington’s (rejected) transport report, commissioned by the Treasury, last December. This proposed extensive road pricing, and planning for less mobility. Hence the Tory intention to increase taxes on domestic air travel, gas-guzzling cars and company parking. Hence the desire to revise overambitious road plans, to limit out-of-town shopping and, most drastic of all, to penalise empty and second homes.

The Tories want to enforce carbon capture on coal power. They want to end onshore wind-farm subsidies and shift electricity tariffs in favour of nuclear power. They are not yet ready to end the Vat bias in favour of (resource-costly) new building and against the conversion of old: Britain could build an Everest out of bricks and stones demolished each year at the bidding of the Treasury. But the message is clear. If global warming is the threat the scientists say it is, then policy must respond.

The first impact of this Tory radicalism is beneficial. It must make it more difficult for the Labour party to outflank the Tories on climate change and should thus make it less excusable for Brown to continue in timid mode. The Conservatives have rejected any idea that a strategy to combat global warming can be cost free. If Britain is to respond to the call of science, it cannot relax into the Green party’s Don Quixote stance, believing that windmills are giants. It has to accept that a low-carbon lifestyle involves painful choices, notably on nuclear energy. If the danger is real, then risks must be taken and money found.

The second impact is more explosive. Cameron has gone out on a political limb. He has rejected advice not to chase policy specifics, not to give hostages to electoral fortune, above all, never to pledge tax increases of any sort. A cunning Labour party could well fight the next election against his offer of more expensive driving and flying and higher energy prices. It could portray Cameron as more caring of fancy theories than of the taxpayer.

Cameron, in Sir Humphrey’s words, is certainly “being very brave”. He might argue that policy on global warming is, in harsh reality, anything but left wing. Making carbon consumption more expensive will hit the poor more than the rich. It involves not just forcing marginal users, which means poor ones, off roads, planes and trains. It means campaigning against the advance to a more mobile, urban culture.

As Ken Livingstone has found in London, a congestion charge drives hundreds of motorists onto buses and Tubes, leaving the streets open to the rich.

The purpose of making air travel more expensive is to end up with less of it for those who can afford only to fly cheap. On a global scale, millions of Chinese and Indians must be discouraged from switching from bicycles to trucks and cars. They must be discouraged from overheating their houses in winter and cooling them in summer. Nothing is more symbolic of a prospering economy than its consumption of carbon. Green taxes are regressive taxes or they will not work. Above all it is the poor they must hurt.

Tories might be less concerned about this than Labour. But higher taxes and more curbs on travel are unlikely to be popular from any quarter. That is why a peculiar responsibility now falls on Brown and his colleagues, who are to publish their own proposals on the environment this month.

They should not sneer at Cameron’s approach but accept it for what it appears to be: a genuine attempt to fashion a policy within the bounds of political possibility.

If Britain’s politicians believe in their high-flown rhetoric on climate change, they should show it. They could hardly do so more emphatically than by opting for bipartisanship. Cameron has thrown down a gauntlet.

simon.jenkins@sunday-times.co.uk

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