One of the most extraordinary features of the ‘cancel culture’ is how well it works. All decent people hate it, but it happens. Why? The key is speed. The bosses of big businesses, universities, quangoes, museums etc. are absurdly frightened by the sudden ambush. Some once-exalted alumnus or benefactor is ‘revealed’ on Twitter as having got money from slavery or worked for the British Empire or used a rude word in 1895.