In the week following the worst terrorist attack in Britain for more than a decade, we talk to the former Head of MI6 (the British Secret Intelligence Service) about terror, security and Trump. Richard Dearlove tells us how he sees the future of NATO and of Europe, and where he thinks the next big threats are coming from. Plus he tells us why he is pro-Brexit and why the Trump administration is not all bad. A lively exchange of views, with Aaron Rapport.