So he leaves without a stain on his cardigan, does he?

The loss of memory which overtakes Mr Blair's ministers at crucial times is one of the medical phenomena of our age

It is possible to imagine the conversation which Mr David Blunkett might have had with the Labour Prime Minister, C R Attlee, some time between 1945 and 1951:

It is possible to imagine the conversation which Mr David Blunkett might have had with the Labour Prime Minister, C R Attlee, some time between 1945 and 1951:

Attlee: Morning, Blunkett. Good of you to come at such short notice. Hear you've been having a bit of trouble in your personal life. All sounds a bit complicated to me, I must say.

Blunkett: It wasn't entirely of my own making, Prime Minister.

Attlee: Just so. Faults on both sides, no doubt. There always are, in my experience. Still, it won't do, you know. Lots of people depend on us. Sure you realised that when you embarked on this business in the first place. 'Fraid I must ask for your resignation.

Blunkett: Tomorrow?

Attlee: No, no, today, of course. Exchange of letters can follow. You know the form. Mutual expressions of regard. Yours ever, Clem. Whole thing needn't take more than a few lines. Well, good luck to you. And if you see Nye Bevan on your way out you can tell him to come straight in. Now he really is giving me trouble.

Three, certainly two, weeks ago it was obvious to some of us that Mr Blunkett could not long survive in office. It was not a question of whether he went but when, and in what circumstances. As things turned out, he went messily, with lachrymose and really rather revolting references to "the little lad" which made it abundantly clear that the former Home Secretary was nurturing his own sense of injury rather than contemplating the misery of others.

The whole sorry business was prolonged by Mr Tony Blair, partly out of a misplaced pride, partly out of a conviction that Mr Blunkett was of political use to him. The Prime Minister has tried to make the best of a bad job by telling us that Mr Blunkett leaves office as a man of integrity, without a stain on his cardigan. Why, in that case, did he have to resign at all? We should try to clear our minds of the sentimental cant which has surrounded this affair from the beginning and continues to envelop it in a soupy fog. For Mr Blunkett does not emerge as a figure of integrity: au contraire, as George Brown used to put it after having lunch at the French Embassy.

There were once two policemen who were discussing money. One of them asked the more senior why he never made a claim for his mileage allowance. "Because, lad," the senior policeman replied, "if they want to screw you, they always do it on your petrol claims."

People still get the sack for making false claims for expenses. Even journalists are not immune from sanctions, even though an acquaintance of mine was once told: "Look, we don't mind you giving dinner to your girlfriend, but just put down 'Police contact' and not 'My girlfriend', there's a good chap." But here too, times have changed.

Politicians have traditionally been expected to observe high standards, though from the 1960s onwards there was a decline. But before 1939 the Welsh miners' MP Mardy Jones was expelled from the House for obtaining tickets to London for his wife and daughter - rather than one to Doncaster for a woman friend who was supposed to be a "partner" but was at the time married to somebody else. Nor was this all. The involvement of the civil service in Mr Blunkett's relationship with Kimberly, Mrs Quinn, clearly went further than approved practice permitted, even if due allowances are made for the additional attentions which Mr Blunkett required on account of his blindness.

Similarly, the Home Office defended Mr Blunkett by all available means over the visa application by Mrs Quinn's nanny. It was this which Sir Alan Budd was asked to investigate. Most commentators, influenced by Lord Hutton's inquiry and, perhaps unfairly, by Lord Butler's as well, predicted that Sir Alan would find that Mr Blunkett had no case to answer.

Mr Blair thought so too, and proclaimed as much. Has the young war criminal no sense of shame? However, knowing Sir Alan (even if only slightly), I did not think he would necessarily give the soft answer. My objections were that he was not an expert on visas and that his terms of reference were too narrow.

There is no suggestion of impropriety in his telling Mr Blunkett that he had found the emails and other messages which contradicted the various accounts given out by the Home Office. It was this communication from Sir Alan which brought about the resignation. Mr Blunkett knew the game was up. But the effect of his departure - combined with the Lords ruling that he had acted contrary to our human-rights obligations - may be that Sir Alan's report will not receive the attention it deserves. It will appear to be last week's news.

And yet, the loss of memory which overtakes Mr Blair's ministers and civil servants at crucial times is one of the medical phenomena of our age. Thus Mr Peter Mandelson could not remember and had to be reminded by Mr Mike O'Brien; and Mr Mandelson went. Ms Beverley Hughes was in a state of amnesia until the old brainbox was jolted by Mr Bob Ainsworth; and Ms Hughes, though eagerly supported by Mr Blunkett, went likewise. Mr Blunkett himself had trouble remembering until Sir Alan Budd found some paper; and now Mr Blunkett has had to take his leave too. It is all slightly reminiscent of the Southwark Crown Court, where various gentlemen can be heard protesting from the dock that they cannot for the life of them remember how half-a-million cigarettes (VAT unpaid) came to be in the back of the white van.

There is no case for maintaining that it was the "right-wing press" which brought down Mr Blunkett. My old friend Ms Polly Toynbee tried to make this out in a somewhat deranged article in Thursday's Guardian. But the Daily Mail quite properly produced evidence which contradicted the Home Office's account of the sequence of events and will presumably be confirmed by Sir Alan this week. It its leader it spoke admiringly of him, and hoped he would soon be back, as did The Sun. Indeed, Mr Rupert Murdoch's papers have proved consistently sympathetic to Mr Blunkett. By the standards of the past, Fleet Street's Finest have gone soft. I stand astonished at their moderation.

The political editors (as political correspondents are now grandly called) of most of the papers consistently got things wrong: they thought Mr Blunkett would survive. They overestimated the power of Mr Blair because of their closeness to No 10. Perhaps they overestimated his loyalty to Mr Blunkett as well, for the Prime Minister could simply have decided to keep the Home Secretary in his government.

The assumption is that, having paid his debt to society, Mr Blunkett will be restored to office after the election. As Mr Mandelson and Mr Stephen Byers have shown (though Mr Byers refused a cabinet job) resignation is no longer regarded as a bar to future office; more as the inconvenient interruption of a career. But the right-wing press did not bring down Mr Blunkett. He brought himself down.