Perhaps this column needs a “trigger warning”, that is to say a warning to the effect that it might make some people uncomfortable. Not making people uncomfortable seems to have become the latest academic fashion.

It is increasingly being used to ban or censor people who challenge an existing progressive consensus, on the grounds that others – and it is mainly students – should not have to experience ideas that might upset them. In this case “progressive” certainly does not mean “liberal” – this philosophy is very illiberal.

Such potential victims are entitled to a “safe space”, it is argued, free from whatever might trigger such unpleasant experiences. A harsher version of the same philosophy labels non-consensual non-progressive ideas as fascist, racist, sexist, homophobic or Islamophobic, and hence proposes to deny them a “platform”, the term for which is “no-platforming”. That means refusing them any forum where they can explain their views.
The banning of anyone who advocates actual physical violence is entirely defensible.