As far as Paris is concerned, Russia’s support of armed proxies in Ukraine and the ensuing destruction of Malaysia Airlines flight MH17 is no obstacle to delivery of the first of two French-built Mistral-class ships . And, for the moment, options on the delivery of the Vladivostok’s sister ship next year remain open, subject to Russian behaviour. Which raises the question of how bad Moscow’s behaviour has to become force a cancellation.

With Russia embarking on its neo-imperial enterprise, common sense militates against delivering tools of war that could put Nato allies at risk. So why is the deal proceeding, and how could the French be brought to cancel it?

Shortly after Russia’s invasion of Georgia and President Barack Obama’s election in 2008, the US proposed a reset of relations with Moscow. Few western leaders took up this suggestion with as much gusto as Nicolas Sarkozy, then French president, with the sale of two naval assault ships of the new Mistral class for €1.2bn. The Mistral, although barely armed, has great military value as a highly versatile expeditionary command post, helicopter carrier and landing craft platform. It proved its worth when the French used it in the Libyan campaign of 2011, and as the pivot of the maritime component of Nato’s rapid response force.