For a broadcaster with a reputation as a bit of a rottweiller, John Humphrys is the picture of contentment and good humour face to face. Humphrys was speaking today at an event organised by Kaizo PR, and offered his insight into how the rise of social media has changed the nature of news. 

In his view, there have been two dramatic developments over the past fifty years: the death of deference followed by the end of privacy. He described how deference led Britain's newspapers to publish not a word about King Edward VIII's affair with Mrs Simpson – and how the American media similarly kept quiet about JFK's numerous affairs. British television and radio interviewers once asked government ministers what they'd like to talk about. The world changed during the Sixties, but for Humphrys the defining moment was the fall of Richard Nixon. He foretold the president's resignation live on the BBC's first live interview by satellite link. 

I asked him whether the rise of 24 hour news and social media hasn't made us far too angry for our own good. I gave the example of the news this week that children in Britain are far less likely to die violently than thirty years ago – contrary to the impression we get from the media and Tory politicians that Britain is a violent and broken society. How, I asked, could we have a reasoned debate when we're all so worked up? John pointed out that politicians didn't want to have a reasoned debate: they want to get us worked up so they can push their own views and policies. 

All this reminds me of a point the Guardian's media reporter Stephen Brooks made on the paper's media podcast recently. He was commenting on the protest on Twitter about the BBC World Service's debate about Uganda's vote on whether gays should face the death penalty. The World Service had rather foolishly carried a headline on its website asking whether gays should face execution.  But Brook was concerned that the storm of protest was all about the BBC, not the outrageous action by Uganda. 

I mustn't give the impression that social media isn't a good thing. The Guardian's victory against Trafigura's attempt to gag the media last year was a triumph for Twitter. Reading Harold Evans marvellous autobiography, My Paper Chase, I thought Twitter would have helped Evans win the fight for justice for Thalidomide victims in a fraction of the time. 

But back to today. Humphrys expressed sympathy for his friend, and former Today editor, Rod Liddle, whose chances of becoming editor of the Independent have been damaged by a similar Twitter storm about allegedly racist comments on a Millwall fans' forum. He defended his friend, saying Liddle wasn't racist. But the Liddle case shows the dangers of shouting off online. Liddle is famously opinionated, and has made a lot of money as a result. He can hardly complain if his job prospects are endangered because of his outspokenness. 

Disclosure: I was invited to today's event by Kaizo PR.