Diplomats at summits are fond of saying: “Nothing is agreed until everything is agreed.” Trump’s brand of diplomacy turns this on its head by breezily declaring that everything is settled when, in fact, nothing has been resolved. Even if the president is right this time and a US-Iran agreement is about to be announced, will it cover anything more than reopening the strait? What about Iran’s nuclear ambitions, particularly its 440kg of highly enriched uranium, and the regime’s surviving arsenal