What went wrong for the western alliance in Afghanistan? Paul Lay and Alastair Benn are joined by John Ferris, author of Behind the Enigma: The Authorised History of GCHQ, Britain's Secret Cyber-Intelligence Agency, to discuss whether liberal states can still carry out effective counter-insurgency operations.

Credit: U.S. Marines search a compound in Afghanistan. Image: Stocktrek Images, Inc. / Alamy Stock Photo