Leading article: Some vital questions of supply and demand

Mankind was always destined to exhaust the earth's supplies of fossil fuels one day. But that day seems to be approaching faster than we previously imagined. Yesterday, the International Energy Agency warned that the global demand for oil this year will be considerably greater than originally estimated. It also warned that oil exporters are operating at maximum limits. Global demand for oil is exploding just as supplies appear to be faltering.

The immediate causes of this year's supply problem are local. Hurricane Katrina severely damaged US refining capacity, and militant attacks in Nigeria have disrupted production in Africa. But the surge in demand is the story of our globalised economy. Countries like China and India are growing rapidly, fuelled by fossil fuels. Our own thirst for oil shows no signs of being slaked either. The IEA estimates that the world's total energy requirements will rise by 50 per cent in the next 25 years. The pressures on supply are only beginning.

The price of crude hit a record high last August, and is now hovering at around $70 a barrel. But the true price is much greater. Our insatiable demand for oil profits some of the most unpleasant and illiberal regimes in the world. Billions of petrodollars have flowed into the coffers of the House of Saud for the past 50 years. Yet that authoritarian regime's only major export, other than oil, has been the virus of Islamic extremism. Another great beneficiary has been Iran, which exports hundreds of thousands of barrels daily. If the crisis over that country's nuclear ambitions escalates, there are fears that President Ahmadinejad could close the Strait of Hormuz, cutting off the flow of oil from the Gulf.

And then there is Darfur. The government in Khartoum has been sponsoring the ethnic cleansing of hundreds of thousands of black Sudanese, but the world hesitates to stop this savagery because it needs Sudan's oil. Russia retains its place at the top table of nations, despite Moscow's increasingly undemocratic behaviour, thanks to its colossal oil and gas supplies. Oil even props up Washington's Latin American bête noire, Hugo Chavez, who controls Venezuela's abundant supplies.

That is the political toll; the environmental toll threatens to put all that in the shade. Every day we learn more about how global warming caused by our burning of fossil fuels is affecting our planet. The polar ice caps are shrinking because of the amount of carbon being pumped into our atmosphere. Rising sea levels, the desertification of vast tracks of our fertile earth, and dangerous weather conditions will be the result. Scientists from Colorado State University predicted last week that this year's Atlantic hurricane season is likely to produce an above-average number of storms because of very warm sea-surface temperatures. There is a risk that hurricanes could once again damage the refining capacities in the Gulf of Mexico. And so the vicious circle of our oil dependency continues.

The response of our democratic leaders to this looming crisis has been pathetic. The US administration is languishing in denial. Our own government pays lip service to the problem, but does little of any value. It was revealed this week that Margaret Beckett, our so-called Environment Minister, feels it appropriate to use a private jet when she could, just as easily, take the train. As a symbol of New Labour's failure to confront climate change this is hard to beat.

Serious efforts to wean our societies off this pernicious dependency on oil and other fossil fuels cannot be delayed. The growing scarcity of oil must be a wake-up call. Let us hope it will not require a global energy crisis or an environmental catastrophe to finally spur us into action.