What if Rupert Murdoch hadn't bought The Sun in 1969? Quite possibly, Neil Kinnock would have become Prime Minister in 1992. Almost certainly, Britain would be less raunchy today. Undoubtedly, the Royal Family would have retained more dignity. Arguably, the Mirror pensioners might not have lost their money. And Manchester United might not have been strong enough to win the Champions League. Or, then again, it might not have made much difference at all.
Of all the programmes in the What If? television series (currently showing on BBC4), the Murdoch question has been the hardest one to answer. On any view of events, Murdoch is motivated by commercial success. He did not get where he is without following trends and going where the money is. So he may appear to be very much the mover and shaker, when his success actually comes from being a dedicated follower of fashion. Although he bought The Sun, is he more of a mirror, showing the world what it is actually like?
With my guests Polly Toynbee, Frank Johnson and Bill Hagerty, I have tried to identify the effect of Murdoch's purchase of The Sun, not just on Fleet Street but on politics and on social attitudes in general. You could argue that if Murdoch had not arrived in Fleet Street and transformed it, then somebody else would have done it eventually. Eddie Shah pioneered modern printing methods, and Robert Maxwell also had it in mind to bring about changes.
But could anyone else but Murdoch have brought about the revolution in our newspaper industry? It required his extraordinary determination to move News International's whole operation overnight to Wapping, under the cover story of starting a new evening newspaper. That dramatic move must have made a difference. And there was no one else who could have pulled it off.
The move to Wapping is, of course, crucially relevant to The Independent. This newspaper was born of a reaction to the way The Times was going. And the possibility for starting up a newspaper existed only because of the change in technology.
Oddly enough, Wapping has not led to a huge flowering of new newspapers. The Sunday Correspondent came and went. Today came and went. We still have a lot of newspapers in this country, but we have pretty much the same ones that were produced in the pre-Wapping era.
How did Murdoch's acquisition of The Sun affect the world of politics? When Murdoch took over The Sun in 1969, it was a left-supporting paper, in the tradition of the Daily Herald, which it replaced. It remained a Labour-supporting paper until it eventually relocated behind Margaret Thatcher in 1979. It was a vociferous supporter of Thatcher, and you could argue that that was just Murdoch sniffing the wind and going with her agenda.
The Sun was always comfortable with Thatcherism: council-house sales, the Falklands War, confronting the unions. And he supported those issues because they were popular - it was not that they were popular because his papers supported them.
But it may well be that it was The Sun what won the 1992 election for the Conservatives and kept Kinnock out of Downing Street. The Sun was relentless in its opposition to the Labour leader, deploying its sharp, funny and aggressive journalism. "If Kinnock wins today, will the last person to leave Britain please turn out the lights," ran the front-page headline. In a close-run election, that might have been enough.
Of course, newspaper people exaggerate the importance of their political views to their readers. On the morning of an election, most of us don't consult the leader in The Sun - or, for that matter, The Independent or The Times - before deciding how to vote. But if, over weeks or months, somebody is presented as a dithering idiot, and it is taken up in the media generally, that is bound to have an effect.
There are other effects on public opinion because of Rupert Murdoch's approach to life. The obvious one would be the Royal Family. Had he been a fervent monarchist, The Sun's way of reporting on the Royal Family, intruding on their privacy and holding them up to ridicule, just would not have happened in his papers. Would it have happened without him?
Similarly, he has been strongly against integration with Europe. With a different boss, The Sun could have been ridiculing Little Englanders for the past 20 years, but instead it has produced headlines such as "Up Yours, Delors" and "Bent Bananas from Brussels". That could be just what sells. It's far easier to be funny by slagging off foreign countries than by speaking up for them. But a convinced anti-European at the News International helm could well have altered the whole national mood. He even persuaded Tony Blair to write a piece in praise of the pound.
Then there is The Sun's effect on attitudes to nudity in pictures, tittle-tattle and celebrity gossip. When Page Three girls came in, it was a shock tactic and widely condemned as at best a gimmick and at worst pornography. Now, the picture of a naked girl scarcely raises an eyebrow. The Sport titles, which, unlike The Sun, have not quite managed to be regarded as proper newspapers, are full of naked flesh. As are any number of magazines, down- and upmarket, and other forms of media.
In Fleet Street, the other tabloids - and even the broadsheets - have had to keep down with The Sun in order to keep up. You get more readers by being more raunchy. The same seems to apply to television. On late-night multi-channel television, in which, of course, Murdoch also has a stake, without tuning in to overtly pornographic channels, you can always find endless programmes of the Undercover Holiday Reps Go Wild in Spain, Drink Too Much and Take Their Clothes Off sort of thing. Was Murdoch the first to spot a trend, a change in morality that was coming anyway? Or did his no-nonsense approach shake us up?
Profits from The Sun gave Murdoch just enough money to get through the difficult years at Sky. Again, you could argue that the Sky technology was going to be developed anyway, but he was the one who actually did it.
But now, football and Sky prop each other up and are mutually dependent. Football has an income stream from television that has allowed our clubs to compete, just about, with clubs in Italy and Spain.
If Murdoch had not bought The Sun and had not been able to set up Sky, then Manchester United might not have had the financial resources to win the European Cup. I think that's a plausible argument, although it's not one I would like to have with Sir Alex Ferguson over a couple of drinks.
Murdoch's rival in the buying of The Sun was Robert Maxwell, who ended up getting The Mirror instead. Had Maxwell got The Sun, one could only assume that he would have kept it as a competitor for The Mirror but as a Labour-supporting paper. One or the other might have gone under because they would have been competing on the same terms for the same market. Whether the Mirror pensioners would have done better under the arrangement is an interesting point.
So what would The Sun be like if Murdoch had not bought it? It's difficult to imagine something quite so aggressive, up-to-date and funny. Its eye-catching headlines are always powerful weapons to have on your side.
In our discussion, Bill Hagerty made the point that Margaret Thatcher always gave the paper full credit, probably too much credit, just to keep it on side. That's one of the things that Blair has picked up on. It may well be that Rupert Murdoch is interested only in circulation figures and in buying more newspapers and more companies. Altering a country's politics or its social attitudes may just be side-effects he is scarcely interested in. He seemed to be anti-Communist until he tried to buy television rights in China. Then his concerns melted away.
"What if... Rupert Murdoch ceased trading?" is not a question we can yet consider with confidence. He has achieved commercially all that anyone else would want to achieve, but so far does not seem to want to stop.
'What if? - Murdoch & The Sun', will be shown next Monday on BBC4 at 10pm