His family’s ancestral seat is the stupendous Badminton Home, established in 52,000 Gloucestershire acres, his eldest brother is the Duke of Beaufort and his very first cousins contain the Marquess of Bathtub. So Lord John Somerset — recognised to chums as Johnson — might moderately be expecting to be accorded a cordial, even deferential, reception at Harrods, ‘the world’s major luxury division store’, as it proudly designs by itself. But not a bit of it: in amazing scenes, the 57-calendar year-outdated was almost ‘frogmarched’ out by safety guards — an indignity for anyone, but perhaps especially traumatic for a member of the aristocracy, even in today’s studiously egalitarian society. The…