It's time for America to "do a little soul-searching," said the local sheriff after the Democrat Congresswoman Gabrielle Giffords was shot in Tuscon on Saturday. "The anger, the hatred, the bigotry that goes on in this country is getting to be outrageous. And, unfortunately, Arizona has become ... the mecca for prejudice and bigotry."
Who knows what was going on inside the head of Jared Loughner, the 22-year-old who has been held for her shooting? But we do know he was politically aware and that he hated federal government. We also know that Ms Giffords had been the target of threats and that her office door and window had been smashed. And when Sheriff Dupnik condemns the "vitriol" that has been emanating from TV and radio about "tearing down the Government", it's worth listening to his argument that "this may be free speech but it's not without consequences".
Ever since the US's broadcasting regulator, the Federal Communications Commission, repealed the Fairness Doctrine in 1987, TV and radio stations have been free to be as partisan as they like. It's not just a right-wing phenomenon but it's fair to say that the most inflammatory voices, such as Rush Limbaugh and Glenn Beck, are on the right. And the more outrageous they are, the more their ratings rise.
Glenn Beck, who has his own show on the right-wing Fox News channel, is now the fourth most admired living man in America, according to Gallup. This is a presenter who's said that liberals want to set up internment camps for patriots and that President Obama is a racist. He regularly warns that violence and revolution are coming to America. In September, he claimed on his show: "I believe these are the most dangerous two years of our republic. Because in the end, in revolutions, the real dangerous killers show up when things start to fall apart."
Words matter. They have a huge influence on the political climate. One critic told The New York Times last year that he was "ashamed and sickened by [Fox News chief] Roger Ailes's horrendous and sustained disregard of the journalistic standards that News Corporation, its founder and every other global media business aspires to." And who was that? None other than Matthew Freud, son-in-law of Rupert Murdoch, founder of News Corporation, which owns Fox News.
Fox News claims to be "fair and balanced" in its coverage of politics, a slogan that draws a bitter laugh from anyone who isn't a staunch Republican. The station is about as fair and balanced as the Daily Mail. And this bias has a lamentable effect on the state of American political discourse.
The US fairness rules used to ensure that all sides of a controversial issue had to be aired in a programme. They don't now. The result is worrying for those of us who believe that knowledge is better than ignorance for the health of a democracy. A study by the University of Maryland, published last month, found there was an exception to the general rule that people who watched more news or read more newspapers were better informed. The exception was those who regularly watched Fox News.
These viewers were shockingly misinformed. They were twice as likely to believe that most scientists don't believe in climate change and that it wasn't clear whether Obama was born in America. The more often they viewed Fox News, the more likely they were to believe these untruths. And the effect wasn't just a matter of partisan bias. Even Democrats who watched the station were more likely to be misinformed.
If America is now as politically polarised as it has been since the Civil War, this is surely one of the reasons. People start with a prejudice, and when they turn on the radio or TV, it's not only confirmed but magnified. If they also read a newspaper of the same political complexion, they can spend their whole life in a reality bubble that's way off the mainstream, but is never pricked. It's dangerous for the condition of politics – and possibly even for the lives of politicians.
Here in Britain, by contrast, you can confirm your prejudices by reading the Daily Mail or The Guardian, but as soon as you watch or listen to the news, those prejudices are challenged by impartial coverage. You would never be told by a TV presenter that Obama was a Muslim – yet the proportion of Americans falsely believing this, nearly one in five, has grown by 50 per cent over two years, and the most popular media source cited for the belief is television.
I know many people here complain the BBC is biased – that it is too left-wing or pro-EU or anti-Israel. But, having spent two years as a presenter of a BBC news and current affairs programme, I can tell you that a huge amount of effort goes into being as impartial as possible. Adjectives are pored over, interview questions are scrupulously planned, and guests are chosen so that every side of the question is represented. We even had to be careful about sounding too sympathetic to pro-democracy campaigners who were being killed in Burma and Iran. If the result is anything less than balanced, it's not for want of trying.
This neutrality in broadcasting is a precious commodity that should not be lightly discarded. The repeal of the Fairness Doctrine in the US isn't the only progenitor of today's viciously polarised politics, but it must be a substantial contributor. If voters' false beliefs not only go unchallenged by the broadcast media, but are inflamed by it, that is bound to encourage political extremes. And it whips up anger and hatred.
So how extraordinary it was to hear Mark Thompson, the BBC's director general, say last month that it might be time to relax the impartiality rules here in Britain, something Rupert Murdoch, owner of Fox News and part-owner of BSkyB, is lobbying for. Why on earth would the head of the BBC want to bring here the coarsening of broadcasting – and polarisation of politics – that we've seen in the US?
It would be a disaster for Britain if the impartiality law were to be lifted. Of course people can read whatever biased trash they like in newspapers or on the net but at least there is a corrective when they watch or listen to the news. This is vital for the proper functioning of democracy, and for the civility of our discourse. Our politicians may disagree with each other, but they don't see their opponents as traitors or stick cross hairs over their constituencies. And let's not pretend that our viewers are media-savvy enough to be able to discount the falsehoods that might appear on TV news if our laws were relaxed. Perhaps the most depressing statistic to emerge from the US is that Fox News is the most trusted news operation in the country. Nearly half of Americans trust it, far more than say the same of CNN or the traditional networks.
Dean Denham, president of Public Policy Polling, which carried out the survey, said its implications were troubling: "That people see the network as trustworthy is worrying in terms of the future of reasoned debate in America. A lie screamed loudly will trump a truth spoken quietly." How very true. And what a lesson for us.