Alan Watkins: There were eras of Wilson and Thatcher. Will there be an age of Brown? I doubt it

All Mr Brown wants is a good long spell in Downing Street

Just before Labour was returned in 1997, a new play was put on in the West End. It was about the election of 1945 and set in the Potsdam Conference after the war. The chief characters were C R Attlee, the Prime Minister, and Tom Driberg, a newly-elected Labour MP (though the play does not perhaps make it entirely clear that Driberg had already sat as an Independent for three years). Even Sir Michael Gambon failed to do justice to the latter's uniquely monstrous qualities.

The work was not intended as a celebration of Labour's return to power. At least, I do not think it was. It was a bright idea based on a possible meeting between unlikely characters. As such, it came off perfectly well. But the audience would keep interrupting: not noisily, or crudely, you understand, but complicitly, as if they at any rate comprehended the point which the author, Mr Stephen Churchett, was endeavouring to make.

I think the audience was reading more into the text than the author was. Thus Mr Tony Blair was seen as Attlee's equivalent, tantamount to a better, cleaner regime. There was, I remember, a similar feeling around the place in 1964. Several events of the early 1960s - various cases of corruption or incompetence involving espionage, the entire Profumo affair - looked forward to Harold Wilson's triumph of decency and straight-dealing, or so it seemed at the time, admittedly a comparatively short time.

In much the same way were the foundations dug for Mr Blair's victory of 1997 partly by Sir John Major and his ministers, but more effectively by Mr Alastair Campbell and his press officers.

I have usually thought it a form of cheating to save my conclusions till last. It is a variety of professional trickery. So it is that I can reveal that the Blair Governments of 1997-2007 have appeared more corrupt than the Major administrations of 1990-97. Nor is it a matter of appearances solely, though these certainly enter into an overall assessment. The governments in question rarely have been more corrupt, judged by any reasonable criteria, than their Conservative predecessors were before 1997.

There is a sense in which New Labour - the phrase is becoming a trifle unfashionable, if it has not already become so - has brought its troubles on its own head. Mr Blair told us when he was in opposition that in government the party would be purer than pure or whiter than white or whatever the precise phrase was.

This was partly smugness. It was also a convenient stick with which to belabour the then government. No politician would ever have chosen seriously to consider the problems involved. He would have produced the phrase: then he would have hoped for the best. This is certainly what Mr Blair would have done and what he went on to do, in numerous connections and on several occasions.

It is what happened and, to a certain extent, is still happening over Iraq. Mr Blair did not take us into war in the Middle East because, unfortunately, he got the evidence a bit wrong. The evidence did not come into it: or, if it did, it was because the evidence, such as it was, was to be used as an instrument of persuasion or coercion.

The age of Blair has been derived from the Iraq war. The two are indissolubly connected. Last week in The Guardian, his indulgent biographer, Dr Anthony Seldon, urged us to look back with gratitude. I am not so sure. The spell since the last war has given us five ages: of Attlee, Macmillan, Wilson, Thatcher and Blair.

To these eras, I look backwards most fondly to that of Harold Macmillan between 1957 and 1963. Most historians would nominate Attlee or Thatcher before Macmillan. In any case, the characteristics of an age or an era are not necessarily the same as those possessed by an individual Prime Minister. The age of Blair is drawing none too peacefully to its close. It is a long drawn out and may still prove a messy process.

Of those I have just cited, Attlee outstayed his welcome, probably because he wanted to impede the prospects of Herbert Morrison, and was christened "Lord Limpet" by the Daily Mirror. Macmillan adopted the pretext of a urinary illness to bring about his resignation: for the post prostate operation was successful and he lived on to the grand old age of 92. Wilson's departure went off as planned, though there were several snags along the way, and the silliest theories about why he chose to take his leave when he did were current as, indeed, they still are. Thatcher's fall was surrounded by the darkest deeds from which the party is only just beginning to make a recovery.

In fact - by which I mean, as people usually mean, in my opinion - Mr David Cameron is only just becoming a possible Prime Minister. We are seeing out the age of Blair. But will there be an age of Brown? So far, it must be confessed, the auguries are not propitious. We have not so far had an age of Eden, Home, Heath, Callaghan or Major. The last of them, to be sure, lasted a surprisingly long seven years. But there is not even a true age of Churchill, for his last phase.

No doubt Mr Gordon Brown does not bother his head with such fancy categories. All he wants is a good long spell in No 10. As far as one can see, it is to be a continuation of the age of Blair, conducted by other means. After all, Mr Brown has long taken his summer holidays at a fashionable American resort. The names Cape Cod and Martha's Vineyard come to mind, though I am no authority on the Chancellor's social habits. He has long professed an admiration for US social arrangements, though I am not clear why this should be so.

It has even been said that Mr Brown should inaugurate, even formally mark, a new age of Brown with a General Election to be held in 2008, or even 2007. There was a change-over of Prime Ministers involving Churchill and Eden in 1955; Eden successfully held an election in seven weeks. Others - Home, Callaghan, Major - have been more cautious. Major chose correctly in 1992, Callaghan wrongly; Home might still have been proved right in 1964 with a bit of luck on his side.

But it is not for Mr Cameron to show caution of any kind. He should tell Mr Brown that the new Prime Minister must go straight to the country and that honour expects nothing else, but he has done that anyway.