The journalist interrogates the ideas of safe space on campus, the psychology of “vindictive protectionism” and the practice of “no-platforming” speakers. In a political culture that is susceptible to polarisation, where social media amplifies grievance and offence, how do we wield free speech? Aaronovitch discusses his lecture with Clemency Burton-Hill. He talks about his memoir Party Animals: My Family and Other Communists on Sunday