There's a tension so deep in how we think about free expression, it should rightly be called a paradox.
On the one hand, regardless of ideology, artists and writers almost unanimously insist that they do what they do to change minds. But the same artistes, auteurs and opiners recoil in horror when anyone suggests that they might be responsible for inspiring bad deeds.
Hollywood, the music industry, journalism, political ideologies, even the Confederate flag: Each takes its turn in the dock when some madman or fool does something terrible.
The arguments against free speech are stacked and waiting for these moments like weapons in a gladiatorial armory. There's no...