Britain’s fighter jets are running missions into Syria, dropping bombs on the Houthis in Yemen, patrolling over Estonia, Lithuania and Romania, close to Ukraine, and guarding our shores from interloping Russian bombers. And yet, the Typhoon final-assembly production line at Warton in Preston has effectively come to a halt. There are no new orders from the Ministry of Defence, and there is a battle going on between Typhoon supporters and those who want Britain’s military to have more American Lockheed Martin F-35 aircraft instead.