Today some 115 heads of government will descend on the Danish capital to try to agree on a global climate deal. They must succeed – even if just to set out broad political principles. If there was ever a time for statesmanship, it is surely now. A lack of action would be shameful – not just because of the risks climate change brings, but because an agreement could be to everyone's benefit.

Yet a deal is looking less likely by the day. The greatest stumbling block has turned out to be the question of financial assistance. Developing countries have been making increasingly strident calls for money on the table – on the basis that they need help to adapt to a low-carbon economy and that they did not cause the problem.

These arguments have merit. But threatening to scupper a climate deal on the question of government-to-government aid is making red lines out of red herrings.