Just who is this sophisticated European statesman? Meet David McAllister. He was last week mooted as Merkel’s heir apparent at Germany’s ruling conservative Christian Democratic Union party conference in Hanover. Bizarrely, however, his supporters at the congress waved banners proclaiming “I’m a Mac!” – for this leader-in-waiting is a not-so-secret Scot. The son of a wartime British Army captain, McAllister is the first dual German-British citizen to hold prominent public office.