In the end they managed to cobble something together. In the frenzied last-minute haggling, enough was done to spare the embarrassment of the world leaders who had gathered in the Danish capital in the expectation of an agreement. But what exactly does the Copenhagen Accord deliver? The regrettable answer is: too little.

Hopes that Copenhagen would yield a legally binding agreement on cutting global emissions were, it is true, abandoned many weeks ago. But what was unveiled late yesterday evening did not even contain a timetable for the signing of a legally binding treaty. This is an IOU without a date for payment.

Nor can this accord be credibly said to lay a clear outline for a successor to the Kyoto Protocol. There were enough promises on finance for adaptation and mitigation from wealthy nations to bring on board poorer developing countries. And President Barack Obama did a deal on the verification of emissions cuts with China, which was apparently enough to assuage Beijing's concerns over its sovereignty.

But what about the transcendentally important question of carbon dioxide emissions? The accord enshrines an aspiration to keep global average temperature rises over the coming century down to C. Yet the range of developing nations' emission cuts under discussion simply do not fit with the best estimates of scientists on the reductions that will be needed to keep temperatures to this level. There is a serious danger that all these torturous negotiations will be rendered meaningless because the sights of the negotiators have been set so irrationally low.

Just as dangerous is the threat of a loss of diplomatic momentum towards a deal. Copenhagen was supposed to be the end point of a long process on negotiating a successor to Kyoto. Now that deadline has been broken, world leaders are likely to be much less reticent about breaking further ones. We are told that the United Nations summit in Mexico next November is now the target for a legally binding deal. But the spectre of the Doha world trade talks looms ever larger: eternal international negotiations on a common goal that never produce anything.

What is the best that can be said of the agreement that was unveiled in Copenhagen's Bella Centre last night? That complete breakdown was avoided and that it gives the world something to build on in future summits. And in the wording on transparency over Chinese emissions cuts, President Obama has something to sell to a truculent Senate when it comes to passing America's cap-and-trade bill. If the United States, the world's richest nation and its largest per capita emitter of carbon dioxide, passes serious legislation to restrict its carbon emissions next year, the logjam of distrust between the developed and developing nations on show in Copenhagen might yet be broken.

Those who argue that no deal is better than a bad deal – that a breakdown of these talks would have been beneficial – are wrong. This process, under the auspices of the United Nations, is certainly flawed, but it is still the best hope for collective global action against this collective global threat.

Yet the awful – and unavoidable – truth is that the world is little further forward in dealing with the threat of climate change than when this summit began. Baby steps away from disaster are not enough. In 2010 we need great strides.