So farewell then, Peter Mandelson?

Peter fought back tears when Cherie told him: "You will always be one of the family." Tony kindly handed him a personally-written strategy showing how his comeback should begin. "In future, you will achieve much, much more with us," Tony assured him.

And within ten months, Peter returned, and Tony took great pleasure in his old friend's rise, crowing that he was "back where he belonged".

This time it is unlikely that Tony Blair, or his wife, will be quite so generous. When Peter Mandelson trolled up to his friend's house in Downing Street at 10.55am yesterday, he thought he would get no more than a flea in his ear. But he ended up out on his ear.

Mr Blair was cold and decisive. Even while Mr Mandelson was sitting in Downing Street clinging to the belief that he could cling to his job, the signals coming from Mr Blair's angry advisors were that the decision had already been made. Mr Mandelson would be resigned.

Mr Blair must feel personally betrayed by the careless, arrogant behaviour of the man - his closest political ally - for whom he had stuck his own neck out and given a second chance.

Now Mr Blair's wisdom in giving that second chance is questioned and his Government's image of being cleaner that the Conservatives is imperiled. In terms of the coming election, though, the damage has been limited by the swiftness of the axing and it will be limited to a further tarnishing of the public's already cynical view of the political process.

With his rise as the architect of New Labour and his subsequent downfall in the home loan scandal of 1998, many millions of words have been written about Mr Mandelson but none of the biographies have come close to understanding his complex character which was on full show again yesterday.

There he was going into Downing Street in the belief that he would keep his job even though he had left the Cabinet 15 months earlier saying: "In resigning and paying such a high price, I hope I have shown politicians not only have to behave well in every respect but they also have to appear to behave well on all occasions."

There he was in front of Downing Street resigning for the second time in two years because of an act of personal folly, yet for the second time in two years he maintained he had done nothing wrong. There he was reading his statement to the media, a man who had courted the limelight yet blamed the media for shining it into too many dark corners.

Yet these contradictions are the essence of the character of this backroom boy who wanted to be considered a public statesman, of a man who is not content with his own achievements because he still felt overshadowed by his grandfather Herbert Morrison. Mr Morrison rose briefly to Foreign Secretary in 1951; his grandson had to at least match that and dreamed of becoming Foreign Secretary after the 2001 election - a dream that contributed to his downfall because the right-wing tabloid press would never allow such a pro-European to hold such a position. Mr Morrison planned the 1951 Great Exhibition; his grandson had to at least match it and so dreamed of a Millennium Dome - a Dome that ultimately led to his downfall because his desperation to fund it took him into too many murky places.

The contradictions continue. In private, Mr Mandelson is warm, humorous and camp, yet in public he appears cold, arrogant and distant. He has a photographic memory for faces, yet twice now he has been caught out conveniently forgetting important details about his own actions.

He is a strategist deeply in touch with the common mood, yet he has no common touch and little common sense. He can devise the most far-sighted vote-winners, like the 1997 election pledge card, yet he blindly believed that the Dome would attract 12 million visitors. He is known as the master media manipulator who spins wonders for his party; yet for himself he cannot avoid the largest elephant trap. He is the arch fixer who has contacts who can smooth any passage, yet he makes enemies everywhere.

He has the ear of prime ministers and presidents but still is strangely drawn to wealthy people like the Hindujas as if they have some powerful spell over him.

He learns lessons from every focus group and opinion poll, but takes nothing from his own scrapes - he enticed £12m out of Rupert Murdoch for the Dome and then found himself as President of the Board of Trade sitting in judgment over Sky Television's takeover of Manchester United; he allowed an unknown businessman to throw him a lavish birthday party and then sold the Dome to him for a knock-down price; he fished £1m out of Hindujas pockets for the Dome and then could not understand the fuss about appearing to intercede on their behalf for a passport.

He designed the Blair Revolution long before Mr Blair knew there would be a revolution but his feud with Gordon Brown, dating back to the death of John Smith in 1994 when he decided that Mr Blair and not Mr Brown would lead the revolution, has done more than any other internal dispute to destabilise the party.

As Neil Kinnock's director of communications, he invented New Labour long before the Labour Party knew that it needed to be renewed. He formed the triumvirate with Blair and Brown which won the great landslide of 1997. Yet the party has never liked him. At best, it has grudgingly tolerated him - as one backbencher said after the election victory: "He is a bastard, but at least he's our bastard."

At worst, it has openly hated him and, on Tuesday night, at the first scent of blood, the backbenchers were dashing to TV studios to criticise him.

And so Mr Blair is his only bridge to power. The improper phone call and the lie to cover it up appear to have burnt that bridge. It would take immense courage for Mr Blair to resurrect him again.

Yet the warmth in which Mr Blair still holds Mr Mandelson could be seen at Prime Ministers Questions yesterday. William Hague agriculturally scythed in, hoping to spread muck onto Mr Blair, but with a quiver in his voice the Prime Minister replied: "Peter Mandelson is more of a man than many of his critics."

It is far too premature to write the obituaries of a political career. The last time Mr Mandelson resigned, one North-East Cabinet member said privately: "It will be a long, long time before we see him back again."

But there he was within ten months.

It has been said that to Mr Blair, Mr Mandelson is like a drug - he needs a fix, a chat, a phone call at least twice a day.

But surely - surely - this resignation means that however close he remains to the Prime Minister, and however valuable the Prime Minister regards his advice, his future visits to see Tony, Cherie and the kids will always be as a friend and not as a political colleague.