A personal anecdote, to begin. In a letter to the press in late 2014, Barry Humphries asked: Has Australia gone slightly mad? I read in the London press of some poor professor in Sydney who has been persecuted and suspended for sending emails to a friend in which he employs outrageous vernacular epithets for race which would be offensive if they were not so clearly jocular.  His reported response to the storm in a teacup which followed this revelation is, unsurprisingly, bewilderment. How could anyone take such deliberate touretting seriously? The answer, I fear, is that there are a lot…