During a debate on the health-care bill that President Obama fought for so long to pass, a Republican Texan congressman named Randy Neugebauer interrupted a fellow representative to protest about a passage he regarded as being too easy on abortion.

"It's a baby killer," he shouted. The words were heard and recorded, although for a while no one was clear who had said them. After Neugebauer was identified, he issued a statement of apology:

In the heat and emotion of the debate, I exclaimed the phrase "it's a baby killer" in reference to the agreement reached by the Democratic leadership. While I remain heartbroken over the passage of this bill and the tragic consequences it will have for the unborn, I deeply regret that my actions were mistakenly interpreted as a direct reference to Congressman Stupak himself.

I have apologised to Mr Stupak and also apologise to my colleagues for the manner in which I expressed my disappointment about the bill. The House Chamber is a place of decorum and respect. The timing and tone of my comment last night was inappropriate.

Not long afterwards, however, he appeared on the Fox News show Hannity and showed that his remorse was limited, at best:

I don't apologise for speaking what I thought was the truth. I believe this bill was a baby killer, and I'm not backing down or apologising for that. The fact that some thought I was speaking about Congressman Stupak, that was what I apologised to him about. But I'm not going to ever apologise for expressing my feelings on something as important as this piece of legislation.

Further reports revealed even more visceral reactions to the health-care bill. Democratic politicians have received death threats from opponents of the reforms. And a brick thrown into a party office in New York State was wrapped in paper on which the late Republican presidential contender Barry Goldwater was quoted: "Extremism in defence of liberty is no vice."

I bring all this up because I believe it is a consequence of the way that America 's much-cherished First Amendment right to free speech has been so abused that it has led to a culture where truth and civilised debate have been elbowed aside. Malicious rumour, disregard for the facts, distortion and plain lying so dominate political discourse that it is no surprise if some individuals move from vicious words to actual actions.

I've mentioned before my encounter with the US right-wing pundit Ann Coulter. This is the woman who thinks "liberals are racists", the French are "a bunch of faggots", only property owners should be allowed to vote, and anyone who disagrees with her is a "fatuous idiot" or "evil".

Now even in America, there are some who think Coulter goes a little over the top. But her books, with such charming titles as If Democrats Had Any Brains, They'd Be Republicans, are still bestsellers, and she is much in demand as a speaker at events for the burgeoning Tea Party movement.

We have no one like her here. "I know," she said to me when we met. "It's horrifying what the Conservatives are in England. You make clear that I'm not one of them."

Never mind the accuracy. Feel the buzz

Far more serious than the insults dished out by the likes of Coulter (and she has plenty of allies on the airwaves) are the downright lies that were perpetrated against Senator John Kerry in the 2004 presidential election. These were thoroughly outlined by Al Franken, formerly a comedian best known for Saturday Night Live, but now Democratic senator for Minnesota, in his 2005 book The Truth (With Jokes).

If you want a shocking read, I recommend it (and you can read my 2006 interview with him for the NS here). In the chapter "How Bush Won: Smear", Franken explains that "at the outset of the campaign Kerry's record as a decorated combat veteran made him seem strong, patriotic and steadfast -- especially when contrasted with Bush's own record of cowardice". So? "It had to go." And go it went.

A group called the Swift Boat Veterans for Truth published Unfit for Command, a book detailing their claims that "John Kerry misrepresented his record and ours in Vietnam and therefore exhibits serious flaws in character and lacks the potential to lead". Eventually, various big beasts of the print media began to unpick these claims, such as this contemporaneous report in the New York Times.

But as Franken writes: "Long before the mainstream press had debunked each and every charge . . . those charges had been played over and over again on Fox, on talk radio, and in right-wing rags, and had burrowed their way into America 's collective brain stem to lay their eggs of pure evil."

He quotes the Boston Globe columnist Tom Oliphant's conclusions: "You know, we've put a million stories in our waste baskets over the years, because they don't . . . check . . . out. Today, we publish, or we broadcast, the mere fact of the accusation, regardless of whether it's filled with helium . . . We served as transmission belts for this stuff without ever inquiring into its accuracy."

The Swift Boat Vets' campaign, which, the NYT found, had "a web of connections to the Bush family, high-profile Texas political figures and President Bush's chief political aide, Karl Rove", could well have cost Kerry the election. And none of it was true.

The comments of a former Harvard Law School professor, Susan Estrich, on ugly rumours circulating about John McCain during the last election apply equally well in Kerry's case: "If this is what a free press means, maybe they should try being a little less free. Or a little more careful."

Brutalised discourse

Don't get me wrong. I'm not blaming the American media (although one does wonder where their much-boasted care with fact-checking is in all this). I blame a culture in which free speech has been so elevated to such sacred, untouchable status that any curtailment of it is deemed intolerable.

And this noble concept is now frequently used to justify the statement of distortions and unproven accusations that would be nipped in the bud by our much more stringent libel laws. I know I am in a minority, but that's one reason I am wary of the campaign to liberalise them here. I certainly believe that the lies about Kerry, for instance, would have been subject to instant legal action in Britain.

When free speech allows for the brutalisation of political discourse, one in which debate gives way to disgraceful name-calling, one that becomes so devoid of respect for the truth -- still less respect for office -- that a representative could see fit to shout out "You lie!" during President Obama's speech to a joint session of Congress last year, or "baby killer", as with the incident last week, it is too easy and small a step for some individuals to think that brutal actions are justified as well.

In the US, that the voice of the "little man", of Joe Six-Pack, must be heard, is a proposition that cannot be gainsaid -- even when what he has to say is vile, hateful, nonsensical and untrue.

Given that Joe Six-Pack has been so vigorously encouraged in this belief, it should not be a surprise if he occasionally thinks that when his words are ignored, his fists will do just as well.

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