Bill Carmichael: Ugly response to gun tragedy

But that didn't stop partisans from the Left cynically using the massacre to score political points.

Even before the corpses of the victims were cold, left-wing commentators were desperately trying to pin the blame for the shootings on the small-government activists of the Tea Party and, in particular, on to former Vice-Presidential candidate Sarah Palin.

They blamed Palin's combative language – which, in truth, is commonplace across all sides of the political spectrum – for inspiring the shooter, despite the lack of any evidence to back up such a theory.

In doing so, they unleashed an ugly wave of vituperation that has seen Palin and others on the Right bombarded with tens of thousands of death threats.

Things became so bad this week that President Barack Obama stepped in to denounce those who are attempting to use the incident in Arizona to make partisan attacks. Whether his supporters take heed remains to be seen.

The main problem with the Left wing narrative that the Right was to blame for the shooting was that it simply wasn't true.

Far from being a Tea Party sympathiser, the accused killer turns out to be a flag-burning, militant atheist who thinks 9/11 was an inside job by the Bush administration.

Such delusions are common on the fringes of the Left, but, in fact, the shooter appears to be a mentally-ill loner without any coherent political views.

And, in truth, we use martial language and military metaphors to describe peaceful political conflicts all the time. Politicians talk routinely of "campaigns" to "target" and political "enemies".

Only this week, I was talking to an activist who told me of plans to "decapitate" the coalition Government by defeating Nick Clegg in his Sheffield Hallam constituency.

He didn't mean it literally – at least I hope not.

Neither is there much evidence on either side of the Atlantic that political discourse has become fiercer in recent years. Anyone who has lived through the Thatcher or Blair administrations here, or the Bush government in the US, should be aware that intemperate and sometimes violent imagery is nothing new.

What we've witnessed in the US over recent days is a sign of desperation.

In spite of – or perhaps because of – the unrealistically high hopes of his supporters, Obama's presidency has proved so far to be bitterly disappointing.

The American electorate turned decisively against the Democrats in recent mid-term elections, and unless there is a major change in mood over the coming months, Obama could well face defeat in 2012.

So, the Left is searching wildly for anything that may spark that change of mood.

If Obama's poll ratings do not improve in the near future, I'm afraid things will get even nastier in the US.

And what is it about strong, independent-minded women that drives the Left bonkers?

Mention Margaret Thatcher's name in the UK and, within seconds, normally sensible people will start gibbering and frothing at the mouth – and Maggie has been out of power for more than 20 years.

Sarah Palin seems to invoke much the same reaction in the US – and in both cases, violent, sexual imagery is often used against them even by supposedly mainstream figures.

Is it a case of old-fashioned, primitive misogyny of weak men who feel threatened by strong, capable females?

Or is there a deeper psychological reason why so many of those on the Left hate women?