It’s not often that I’m listening to a radio programme and I find myself having to pause it – one of the benefits of listening online – to tell whoever I happen to be with the extraordinary thing I just heard. But that happened almost every few minutes while listening to the first episode of Things Fell Apart (Radio 4), the second series of Jon Ronson’s enthralling journeys through the culture wars to suggest the surprising origins of some of our most divisive contemporary debates.