David Cameron’s signing a letter with five other world leaders outside Europe calling on Eurozone leaders to act swiftly to halt the Euro crisis, I believe, marks a turning point in Britain’s relations with the European Union, for worse not better. Just as the use of Zepplin airships and the French Voisin aeroplane to drop bombs from the air at the beginning of the First World War was the unrecognised time in history when the nature of military conflict changed for ever, David Cameron has brought us his own Zepplin moment.

The letter, apparently designed to help shape the agenda for the next G20 meeting in Cannes in November, is a major departure for Britain. This country has been anchored in the EU for the last 40 years, longer than the lifetimes of many readers of this blog. It is unprecedented for a British Prime Minister to join forces with two Commonwealth leaders, in this case Stephen Harper of Canada and Australia’s Julie Gillard, and three others outside the EU to send a warning letter to the main EU member states.

What is in the letter – that the signatories want greater political will behind the Eurozone bailout mechanism and, rather interestingly, greater political integration in the Eurozone – is not really the point. Cameron talking tough on Channel 4 saying: “We cannot go on kicking the can down the road. We need decisive action, swift action to deal with this issue” is more or less par for the course.

What is totally unacceptable is that David Cameron has the incredible brass neck to dare to tell Nicolas Sarkosy, Angela Merkel and the rest of the Eurozone how to run their affairs, while at the same time endangering Britain’s interests in the world. It’s not even as if Britain under the Tory-led coalition were a shining example of economic competence. The IMF is forecasting reduced growth for Britain and hinting that the Cameron-Osborne austerity programme may be going more harm than good and should be slowed down.