We recently mused on the idea of British luxury car makers collaborating on a bespoke, Trump-branded gift for the US president. Of course, there's a long tradition of special vehicles for state leaders, and indeed many of them have been true petrolheads. 'The Donald' may favour big V8s, but the first official car of any US president was powered by steam. It seems it was secretary of war William Taft who instigated the government's purchase of two White Pullman tourers in 1907.