1. “You can’t shout fire in a crowded theatre.”
This hackneyed faux-truism is the Expecto Patronum of squishy liberal apologists. That is, when the going gets tough and they’re forced to do that difficult thing – defending free speech – they reach desperately for this magical formula, rather as Harry Potter does when faced with the Dementors. Once the phrase has been uttered, they seem to think, the argument has been made for them and the nasty, scary problem will go away – as no doubt the Lib Dems’ Vince Cable did when he used it in the most recent edition of BBC Question Time.
But the analogy just doesn’t work for at least three good reasons.