There is little more cringe-making than an A-list superstar reduced to a sideshow freak, willing to be humiliated for big bucks and sending themselves up at every opportunity. I used to cringe whenever Elton John appeared in those TV ads for Royal Mail (or whatever it's called these days). There he was, the man who wrote "Your Song", the love anthem of the 20th century, flouncing about like some camp postie, urging us to send presents to ourselves. Foul. It's not like he needs the money.
Ageing rock stars are not the only ones who risk this bleak future. David Cox's recent New Statesman cover story set me thinking about what Tony Blair will be equipped to do after years as an under-siege, world-famous PM. In my imagination I see a 21st-century brat pack emerging in a couple of years' time. Picture the scene: Vegas, the tackiest venue in the western hemisphere. Cue flashing lights: "Live tonight! Clinton, Bush and Blair". George Bush would be up for it. Hey, the chance to wear cowboy boots and chaps, to say "bad guys" and "he's wanted dead or alive" for a huge pay cheque - right up his street. And so long as the show was fully scripted, and an autocue visible at all stages, even he couldn't go wrong.
Bill Clinton already does the rounds, interviewing co-celebs on TV, giving "I was right all along" talks for a hundred K a time. I saw him give a Dimbleby Lecture a couple of years ago, and Clinton is hot. He strides leisurely to the podium, wearing that you-all-want-me look. Clever, greying women mentally undress him when they are supposed to be considering his work in Bosnia and Northern Ireland. He has no shame, he is good with audiences . . . he's a made man.
Unfortunately for my brat pack idea, Cox is certainly right on this: Blair would rather renationalise the railways than risk looking tacky. He's wrong, though, to suspect the PM's ability to be "at least as witty as Rory Bremner". Times may be bad and jokes thin on the ground on topics like top-up fees or the Hutton inquiry, yet Blair remains the most brilliant deliverer of (faux) off-the-cuff gags of his generation. I've sat in the hall at every one of his party conference speeches as Labour leader. The moment the lights touch his make-up - he's off.
Perhaps Blair could give master classes on performance technique to Rada students.
Many ex-politicians tuck themselves away in company boardrooms. That's not for Blair. Like David Beckham, he has worked too hard on his global brand image to swap lunch with Kevin Spacey for lunch with Kevin from accounts.
What will happen to the Labour Party when he resigns is more important. Recently, a woman approached me and asked if I'd like to join her new movement. She has launched a kind of reclaim-the-party party. As a member of a north London constituency party, she is proposing a coup d'etat to mirror the one pulled off by Blair, Mandelson et al.
Like Ken Livingstone, she told me, disgruntled socialists should not tear up their cards; we should rush to rejoin new Labour. We should swallow hard, pay our dues and join a party we now hate - in order to change it into something better.
I think she has a point. After all, isn't that exactly what today's government ministers did when Neil Kinnock was leader? Straw and the others all nodded and muttered and told fellow party members: "Yes, we believe in nationalised railways. We will end free-market madness in schools and health." Then, when the time was right, they all jumped up together and shouted, "Ha ha, fooled you! Now we run things, so there!"
They've undone everything the party they joined actually stood for. It's like crossing your fingers and saying "nah nah nah nah nah" later on. Anyone up for it?
