In 1974-75 Encounter magazine ran a series of pieces about the differences between British English and American English. The likes of Constantine FitzGibbon, Robert Conquest and D.J. Enright wrote at length, as they explored what was being termed Amerenglish. But the most succinct and incisive comment came from Jan Morris, whose entire contribution was this:

Across the sea the electric message hums:
Asses is donkeys – arses is bums.