Where is the difference between moderation and censorship on tech platforms? Anne McElvoy asks the author of “Dangerous Ideas" whether social media giants were right to ban Donald Trump and if speech should be free even if it’s offensive? The human-rights lawyer also talks about working with asylum seekers and picks a previously-censored book to take with him to a desert island.  Please subscribe to The Economist for full access to print, digital and audio editions: www.economist.com/podcastoffer   See acast.com/privacy for privacy and opt-out information.