It was Herald Sun cartoonist Mark Knight who tipped me over the edge. To be fair, he wasn't wholly responsible. If it wasn't for all the lunacy that preceded him, I probably would have dismissed his cartoon as just another Herald Sun atrocity, more a piece of Murdoch-madness to be mocked rather than trigger for outrage. But context is everything. And after days of sanctimonious blather about freedom of speech and the Enlightenment values of Western civilisation, his was one pencil-warfare cartoon too many.