“ROCK STARS”, said Homer Simpson reverently. “Is there anything they don’t know?” As ever, the yellow-pencilled master of innocent irony hits the nail on the head. That, indeed, is one of the great questions of the age. Is there any area of policy, morality and international finance that does not need the input of people whose core talent is singing loud songs and simulating sex with microphone-stands? Does the wisdom of the ages reside in Hey Jude? Is there any point in argument and calculation, or is it better to punch the air and obey the dishevelled figure of Johnny Borrell, the Razorlight frontman, in a white vest howling “Sign the f***ing petition!”?

I do not condemn Live 8. I am quite glad it happened. Its heart was in the right place. It did not “rock the world”, nor was it, as the Coldplay idiot said, “the greatest thing that’s ever been organised in the history of the world”. It was a short-notice summer concert, attended in London by 200,000 people: 20 per cent fewer than those who demonstrated in Edinburgh on the same day, or the crowd who sat on Southsea Common in the rain to watch the Trafalgar 200 commemoration. Live 8 was globally visible because TV executives fawned on it; it had one stunning coup de théâtre in the presentation of the dignified young agriculture student whose life was saved by Live Aid money. It made its patrons feel good, and its multimillionaire performers feel even better and more able to sell CDs and downloadable ringtones. It may, just possibly, make it harder for G8 leaders to sideline Third World poverty. Any who do choose to do so, however, will be calculating correctly that the emotion of a pop concert is ephemeral.

So on balance, good luck to Live 8. But the thing that does stick in my mind is unease about the new role of pop stars in politics. When I grew up as a Beatle-crazed teenager the rules were simple: the idols of youth inhabited the dangerous rackety fringes of the public world. That was why we loved them. When the young Mick Jagger was interviewed on TV he was treated as a weird new species. When Harold Wilson cautiously awarded the MBE to the Beatles, a dozen medal-holders, including a wartime RAF hero, sent theirs back, and a Canadian politican said he didn’t want an honour that “put him on the same level with vulgar nincompoops”. Which was a bit silly, but it showed that we knew where we were. Fun was fun, public service was different. Rock stars could lead their sexually and narcotically wild lives in peace because they held no responsibility. Protest songs like Bob Dylan’s Masters of War had all the more clout because those who sang them stood apart. Elected leaders kept a wary eye but never wanted to change places.

Now, so bereft are we of political inspiration that rock stars rule the roost and loftily patronise elected leaders. Bob Geldof told the Canadian Prime Minister Paul Martin not to bother coming to the G8 sumit unless he signs up to Geldof’s assessment of how much GDP he should devote to foreign aid. “Stay at home. You’re not welcome unless you are prepared to do something finally and irrevocably on behalf of the poor of this world.” Our own Prime Minister, host of the summit, did not rebuke Geldof for this discourtesy but was photographed grinning happily with the Boomtown Rat’s head resting on his shoulder. Meanwhile, Bono says “I represent a lot of people in Africa who have no voice at all” without consulting any of them; George Bush and Condoleezza Rice queue up to be photographed with him.

Politicians are thrilled, not insulted, to be compared to rockers. If you’d told Macmillan he was the Tommy Steele of politics he would have been quite hurt; Churchill never confused himself with Vera Lynn. But when Bono called Blair and Brown “Lennon and McCartney” they simpered with delight. At the Hyde Park concert Kofi Annan, Secretary-General of the United Nations, felt he had to turn up with a humble “thank you on behalf of the poor ” to a crowd who had won a cheap draw for a celebrity concert. Meanwhile, Live 8 stars kowtow to nobody and apologise for nothing: they went home with a warm glow, global free publicity and Hugo Boss goodie-bags packed with £3,000 worth of free gifts to add to their unthreatened wealth. Robbie Williams used the opportunity to proposition a pretty BBC reporter with: “There are two messages: Make Poverty History and Get Robbie Laid”. Laughs and cheers all round.

I suppose this may conceivably re-interest a generation in democracy. You could argue that the only bad thing is oversimplification: people whose main skill is creating a magical atmosphere around themselves should not railroad people who have to sit round tables making hard, complex decisions in an imperfect and often boring world. But you could say that emotion has its place: if real power stays where it belongs, what matter if a bit of stardust is sprinkled?

What really bothers me is that this relationship of pop and politicians is a two-way street. The more they mix, the more rubs off. Ministers now long to be rock stars. Party conferences are staged with theatrical pizzazz to create that magical atmosphere around the leading personalities. Our Prime Minister’s speeches are song lyrics, moody and emotive, with verbless riffs and a calculated voice-break. Like rock stars, politicians have discarded the concepts of disgrace, apology and atonement, and expect to be forgiven for dodgy behaviour (think Mandelson, think Blunkett) simply because they are stars. They are even losing the old upright horror of sticky gifts and goodie-bags (consider Mrs Blair’s ill-judged profiteering, or the Prime Minister’s taste for free holidays). A heady feeling is in the air: it’s all showbiz, all razzle-dazzle.

But it isn’t. Sometimes Bob Geldof starts to look like the most serious politician around. And if that isn’t worrying, I don’t know what is.

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