As the world’s leaders put the finishing touches to their proposals for restoring growth to the global economy ahead of this week’s London meeting of the G20, there is one official body that wishes them only failure in their endeavours. The UK’s Sustainable Development Commission publishes a report tomorrow – Prosperity without Growth? — arguing that “the pursuit of growth has had disastrous environmental consequences. In the last quarter of a century, while the global economy has doubled, the increase in resource consumption has degraded an estimated 60% of the world’s ecosystems and led to the threat of catastrophic climate change”.

In that familiar melange of hyperbole, manufactured statistics and prognostications of the end of the world as we know it, we might spy the handiwork of Sir Jonathon Porritt, Bt, chairman of the Sustainable Development Commission. I suspect, however, that Porritt would have preferred something even more radical. The report appears not to mention at all what he considers the chief cause of “excessive economic growth” – humanity’s perverse desire to propagate.

Last month the blathering baronet told this newspaper: “I think we will work our way towards a position that says having more than two children is irresponsible. It is the ghost at the table. We have all these big issues that everybody is looking at and then you don’t really hear anyone saying the ‘p’ word.” Porritt is a patron of the Optimum Population Trust, which at its annual conference last week again proclaimed its “target” of seeing the population of these isles halved – for the greater good, of course.

I don’t know where Porritt gets the idea that nobody is saying the “p” word. Phil Woolas, the immigration minister, has explicitly said that we must limit our numbers, while David Cameron has suggested that Britain needs a “coherent strategy” on population. The really odd thing, in fact, is that the enthusiasts for population control are given any political credibility at all.

In the 1960s they based their campaign on the notion that there would be mass starvation in Africa and the subcontinent unless those countries learnt to cut back the size of their families; or, worse, they would invade the developed world in their quest for food. The World Population Emergency Campaign ran advertisements in the United States showing a photograph of Africans with grasping hands, with the payoff line “People will not passively starve. They will fight to live”. The idea of the campaign was not to feed them but to make them disappear.

In fact, the past half-century has seen an end to mass starvation in the evermore teeming subcontinent, with India even becoming a net exporter of food thanks to the so-called green revolution heralded by new agricultural techniques which the unreconstructed Malthusians never even contemplated.

Without even blinking, the population control freaks have turned this complete defeat for their intellectual argument – such as it is – into a new threat to scare us with. They argue that as the billions in Asia become ever wealthier, they will use up too much of the world’s resources. Their crime, it seems, is not to have starved to death as they were supposed to. Last year’s sharp spike in food and oil prices was hailed as the warning of dire shortages to come. Yet what has happened? It swiftly emerged there was never any physical shortage of oil; just a frenzy of speculation by traders wrongly anticipating a supply crunch. As for food, it took almost no time for farmers to step up their production, encouraged by the higher prices. That is how markets work, if only politicians will let them.

This, of course, does not answer the latest proposition of the population control freaks: people breathe, which, unforgivably, produces CO₂. Down the years the anti-humans have always been skilful in adapting the fashionable concern of the day to their own peculiar obsession. In the cold war they argued that an uncontrolled surge in young men in the Third World would be prey to the recruiting sergeants of international communism. Nowadays they argue that the same supernumerary youngsters are the future foot soldiers of Islamist terrorism. This is their eternal wail: cull or be killed. The population control movement is nothing more than an idea in search of an argument.

Porritt has now answered the critics of his recent remarks about the link between population and climate change. In his blog he writes: “In China it’s about 4 tons [of CO₂ person per annum. It soon mounts up. Were it not for China’s ‘one-child family’ policy (which is certainly very controversial), there would be as many as 400m additional Chinese alive today – with a combined annual carbon footprint of around 1.6 billion tons of CO₂!"

Note how he skilfully shows his support for the policy of the communist dictatorship of China – involving, as it must, forced abortions and a grotesque abuse of the most basic of human rights – while graciously conceding that it’s “very controversial”. He insists he’s not remotely suggesting any such policy here – and last week a similar reassurance was communicated via the BBC Today programme by his OPT colleague John Guillebaud, emeritus professor of family planning at University College London.

What, then, are they suggesting in order to reduce our own population by half? They advocate a policy of no net immigration. Brilliant: not only is that completely unenforceable under our European Union treaty obligations, but immigration is in any case merely a transfer of population, not a reduction in the global total. If there are more Poles here, there will be that many fewer in Poland.

Next, they advocate greater use of contraception and yet more sex education, as if there might be vast numbers of British women who still think babies are found under gooseberry bushes. Al Gore, America’s leading exponent of the green terror, argues that “we know how to stabilise world population” because “population experts know”. Leave aside the fact that if we wanted to “stabilise” the indigenous population of Europe we would be promoting natalist policies, since our numbers are actually in sharp decline; the truth is that the “experts” don’t really know how to “persuade” people to have smaller families.

As Nicholas Eberstadt points out in his paper Too Many People?, the past quarter-century has seen an almost identical drop in fertility levels in Mexico and Brazil – during a period in which the government of Mexico sponsored a family planning programme expressly committed to reducing its population while the Brazilian government did no such thing. Yet now the Brazilian fertility levels are below those of Mexico.

The point, informed by common sense and normal human empathy, rather than the soulless mechanicism of the population planners, is that individual families have the number of children they want to have for the most personal and local of reasons.

The most prominent British advocates of population control should really be able to understand this. Professor and Mrs Guillebaud have three children. The Duke of Edinburgh, who last year declared there are “too many people”, is a father of four; and what of Stanley Johnson, author of The Population Problem and World Population: Turning the Tide? He is best known for producing a son called Boris but, despite appearances, Boris is not a clone of Stanley – he is one of six children produced in the traditional fashion.

A period of silence from the population control freaks would now be most welcome.

dominic.lawson@sunday-times.co.uk

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