These days, every official visit, every summit that involves the President of the United States seems like a mad scramble to keep the leader of the Atlantic Alliance on board. But what if it’s just too late? Last month, leaders left France thanking their lucky stars that Donald Trump hadn’t taken a big bazooka to the G7 Summit.In Ankara, a darker Donald threatening to pull all US troops from Europe, cut trade with Spain and blasting Nato for its unwillingness to join his war against Iran. He claimed he wouldn’t have even shown up but for his friend Recep Tayep Erdogan hosting. Putting put-downs and popularity contests aside, real lives are at stake.

How do allies go faster in providing defence systems against Russia’s cruise missiles lobbed on Ukraine? What if Vladimir Putin, whose citizens are feeling the pinch from Ukrainian drones targeting power and fuel supplies, decides to go for broke and test the resolve of frontline European states?