At least the turf this issue – the purported opposition to earmarks and pork that Palin is supposed to share with McCain – is being fought over is a public policy issue rather than all the personalised stuff which just puts the Democrats and the media where the GOP want them. But Obama’s reluctance to use the words “lies” and “liars” shows he knows the score. He’s being criticised for that by liberal bloggers, who are cheering on the media “fact checking” exercise.

But all this truthiness is also at great risk of playing into the GOP’s hands – because it reinforces the equation of the media and blogosphere with the Democrats Rosen identified as the tactical positioning the Republicans want – and which George W. Bush reinforced with his claims about “the angry left” in his RNC video link. The culture wars schtick works – because the America of Wal-Marts and small town “values” has more electoral power in the swing states that count than the wonky redoubts of the blue staters. And a lot of those voters – who don’t source their news from the internet but from cable tv – and get their analysis from others of like mind in their own circles rather than bloggers, commentators and wonks – are seeing what McCain wants them to see – a feisty outsider being beaten up by the Beltway elite. Hence McCain’s polling gains, among other demographics, with white women.

Intelligent commentators realise all this. But what no one has seemed to be able to sketch out – in an electoral landscape where the swing states are rustbelt white Reagan Democrat central – is a compelling political and media strategy to rebut and counter it. Crying “truth” and calling time on lies just isn’t enough in a postmodern political world. Anyone remember SwiftBoating? What’s certain is that McCain’s mob have worked out how to game not just the media but also the liberal blogosphere.

Elsewhere: An interesting perspective on all this from sociologist and blogger Andrew Perrin at Scatterplot.