TB: I think you're right in that case, and indeed I think there were long faces among some of the Labour ministers. Chris Smith wrote about that, saying it was all a ghastly mistake, that picture of Blair with Gallagher. On the other hand, John Lennon claimed afterwards that he'd won the 1964 general election for Harold Wilson. That picture of Wilson with the Beatles went round the UK electorate, and when Wilson sneaked in, in the autumn of that year, Lennon said: "We did it for him."

IB: But I wonder if the electorate has become more sophisticated in reading those sorts of things - maybe when Wilson did it, it did contribute to some notion that he represented modernity, but now it's different.

The other thing with pop and rock music is that it's grounded in rebelliousness. What's funny for me is this false consciousness. It's all about being rebellious and against authority, but on the other hand it's so bound up with selling stuff and consuming stuff and keeping the whole wheel of the consuming, credit-ridden economy going, making us want things.

DJ: This was of course the most privileged generation in history, the one that was rebelling in the 1960s. They hadn't had to fight a war, for one thing. Materially, they'd never had it so good. And yet they were the ones who rebelled. So there's something a bit false about that in the first place.

IB: But to be fair, there's a similar thing in classical music, because when we look at classical music and analyse musicians in the past, we like to feel that they were producing something that went beyond the desires and needs of their patrons in the same way that we do with painting. We like to feel that, when Velasquez painted the Habsburgs, or Goya painted the Bourbons, he was making some sort of radical comment about them, because he wasn't really taken in by it. It's the same with music. But actually a lot of art is bound up with patronage and with the current social and economic order, it's bound to be like that. The question is how it can get beyond that.

TB: True. Politicians today watch television like everyone else, and they know that every Saturday night, and on many other nights, there is in effect a kind of karaoke competition. It started out as Pop Idol, then it was The X Factor, now we've got Strictly Come Dancing, where music plays a hugely important part, and what do they see? They see that millions of people watch, and millions of people vote. This is democracy 21st-century style. Where Joe Public really participates in an electoral process with enthusiasm, even pays for the privilege, they're voting for their pop idol, or whoever they think ought to win X Factor. Whether we like it or whether we don't, this is the way the world is going.