It was honest of the Government to admit yesterday that it might fail to meet its target for reduced carbon dioxide emissions in 2010. It was also largely irrelevant. This target was not an international treaty obligation, but a self-imposed goal established in the hope that, by meeting it, Britain could claim moral leadership by example in climate change negotiations. Britain is, probably, on course to meet the more modest emissions reduction targets set out in the Kyoto Protocol — but even these mean little. As long as global efforts to cut carbon emissions are confined to the framework of that protocol, they are doomed to be of little consequence.

It is simple common sense to note that since failing to impose even nominal carbon reduction targets on major developing economies, and failing to persuade the US of its fundamental premises, the Kyoto approach to climate change has been emasculated. Russia’s recent tactical decision to ratify the protocol is more about political opportunism than environmental awareness. After the Kremlin’s decision, Kyoto will come into force on January 1 in the 127 territories that have ratified it. But no purportedly global climate change agreement can be truly global, or effective, without American support. As senior government officials admitted yesterday, winning that support is their most pressing challenge if the decision to make global warming a priority of Britain’s G8 presidency is to yield results.

Climate change and its consequences are still poorly understood. There is, nonetheless, a broad scientific consensus as to its causes (by no means all man-made) and effects (not necessarily apocalyptic), to which Washington is showing welcome signs of lending its support. Political consensus is harder to come by, and President Bush remains adamantly opposed to mandatory carbon emissions limits — hence Tony Blair’s call for a new treaty that would exclude such limits but would at all costs include the US as a signatory. Critics will accuse him of letting Washington off the hook, and in the process squandering his political capital. In fact, it will be put to good use. US rejection of the Kyoto approach, which long predates the Bush Administration, is based partly on national interest, but also on the sound principle that the only long-term solution to the problem of accelerating greenhouse gas emissions is to wean the world off carbon-based energy sources; and that the fastest, cheapest route to this goal is to invest in renewable energy technologies rather than complex carbon-trading and regulatory schemes.

The Government should therefore recognise the significance of US backing for fuel cell and other non-polluting technologies. These technologies will be crucial in coping with the exponential economic expansion of China and India, where the roots of future pollution problems and solutions surely reside. The US and Europe have much more to do, but a reasonable start is to concede that the Kyoto Protocol remains gravely flawed and unequal to the challenge it addresses. An alternative is overdue but welcome.