But seriously I do understand the issue with the Times. Let's discuss over country supper soon. On the party it was because I had asked a number of NI [News International] people to Manchester post endorsement and they were disappointed not to see you. But as always Sam was wonderful (and I thought it was OE's [Old Etonians] were charm personfied!) I am so rooting for you tomorrow not just as a proud friend but because professionally we're definitely in this together! Speech of your life? Yes he Cam

– Text message sent from Brooks to Cameron on 7 October 2009, on the eve of his Tory conference speech

Just 87 words, the text from Rebekah Brooks to David Cameron is nevertheless as densely revealing, as packed with human drama, as the finest, most compact poetry – with added cringe value.

It plunges straight in, part of an ongoing exchange and a tense one at that. Cameron appears to have conveyed his displeasure over a story in that day's Times, perhaps the one claiming that the Tories planned to pack the Lords with a raft of new appointees (paywall link). But Brooks plainly has issues of her own and has told the Tory leader of her irritation that he didn't turn up at the News International reception at that week's Conservative party conference. Brooks insists she accepts Cameron's apparent apology – though with the passive-aggressive rider that she had gone to great trouble, that people were disappointed by his absence and a little reminder that she had expected better treatment given the Sun's "endorsement" a week earlier.

But no matter, all this can be rectified at an imminent "country supper", a phrase that will instantly rank alongside and surely outstrip Francis Maude's "kitchen supper". The phrase is delicious, concisely capturing the entire culture and chumminess of the Chipping Norton set, its elite habits and its remoteness from the way most people are living in austerity Britain. Like Raisa the police horse, it shows just how close Cameron and the Murdoch chief executive were – and what rarefied, monied bubble they both inhabited.

Next comes the praise for Samantha Cameron, who had obviously attended the Murdoch bash as a Cameron surrogate. Brooks compliments Sam for her charm – thereby revealing her own much-vaunted possession of the same quality. Many will find this and the lines that follow too blatant in their sycophancy to be charming, but Brooks's success suggests it had long been effective.

Readers of Tatler or Horse and Hound may sniff slightly at the language. Is it not a trifle gauche to refer to Old Etonians at all, let alone as OEs? Is not the phrase "country supper" itself a little embarrassing, the sort of thing one certainly has and enjoys but does not refer to so explicitly? And aren't all those exclamation marks a little déclassé?

But the killer line is yet to come. Brooks is not just Cameron's "proud friend" but his explicit political ally, even co-conspirator: "professionally we're definitely in this together," she declares with an exclamation mark, surely referencing then shadow chancellor George Osborne's speech the previous day. "We're all in this together," he had said. If Cameron and Brooks were not all in it together before this text was made public, they are now – up to their neck in it, in fact.

The irony is that that phrase of Osborne's was meant to show off the Tories' fair-mindedness, their spirit of shared sacrifice. But this text from Rebekah Brooks skewers that notion, already dead, once more: it shows Cameron as exceptionally close to the top echelon of a corporate empire, permanently mindful of its concerns. No wonder he squirmed as it was read out.

The closing line, as Brooks sought to pep Cameron up for his leader's speech – "Yes he Cam!" — is telling too. For those very words were the headline on the Sun's coverage of that Cameron speech the next day. Papers always deny they decide headlines on stories in advance, that they fix their view of events before they have happened – but this suggests that in the Brooks-era Sun, that was exactly what happened. At least when it came to doing a favour for a cherished member of her country supper set.

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