Twenty-five years ago, Britain returned Hong Kong to China. The handover was based on a promise the city would retain its high degree of autonomy. That pledge now lies in tatters.  Host Anne McElvoy asks Chris Patten, the last colonial governor, why Hong Kong’s nascent democracy was thwarted. Sue-Lin Wong, The Economist’s China correspondent, tells Anne how China tightened its grip on Hong Kong. And, exiled activist Nathan Law ponders the future of the pro-democracy movement.  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.