My own perception has always been that American English was the language of the hedgerow and the gutter, where the transatlantic emigrants had been sleeping before their desperate abandonment of their native climes, and that the English of the British Commonwealth (excluding the antipodean convict colonies) was that of the nobility, who took the best of Norse, German, French and AngloSaxon words so that poetic and conceptual nuances could be more finely expressed.