He came and he gave without taking, as Barry Manilow presciently put it, but is it possible that Oh Mandy could come once more? More than possible, indeed, is it essential to Ed Miliband's chances of surviving as Labour leader for more than a couple of years, let alone of forming a government, that the noble Lord Mandelson rises from the dead once again?
Today, in what I hope proves the first of many positively final comeback appearances, the Barbra Streisand of Westminster is back where he belongs, centre stage, after last night's Hannah Rothschild documentary. Whether Little Ed caught the show may have depended on the new baby's sleeping habits. But you suspect that, despite having jettisoned Mandy with a single line during that endlessly thrilling leadership campaign, he had a glance.
If so, he'll have seen nothing new. There is nothing new to see, after all, in the most beguiling operator of this political age, or any in memory. We know Mandy so well in every regard, from the vanity and roguishness to the fiendishly acute mind churning beneath the self-parodic, camp façade. Ed Miliband knows him better than most, personally and professionally, strengths and weaknesses, and if he doesn't have regrets about archly dismissing him with "we all believe in dignity in retirement", he is less smart than I assumed.
In an age when politics travels at warp speed, a new leader has little time to establish the persona that defines the leadership. Absurdly apocalyptic as this may sound, with Labour level or marginally ahead in the polls, the clock is close to beating Ed already. His legitimacy is questioned by both factions heading inexorably for a civil war to make the Tory one over Europe look like an arcane procedural squabble about parking regulations in the transport ministry of Camberwick Green. All that binds Blairites and Brownites is the shared belief that Ed is callow, shallow, directionless and not properly elected, and that he can be taken out before the next election.
Ed Balls cannot disguise his contempt, understandably given the brutality with which the new leader ostracised him at Home Affairs, while the loyalty of his missus Yvette Cooper is also, to put it gently, in doubt. His shadow Chancellor Alan Johnson, although the right choice as the least hideous option on offer, is proving an ineffective match up against George Osborne, and appears to regard himself as a freelance operative. And then there is some unfinished family business. By anonymously briefing that he isn't quite done with his own leadership hopes, David Miliband makes his ambition to settle a fraternal score almost as naked as the human forms in that painting in his Primrose Hill sitting room.
Harold Wilson survived as leader in a wickedly disunited Labour party, but by cunningly setting his enemies against each other; not by giving them common cause against him. If Ed doesn't exert some control over the uncivil warriors ranged against him, he will either be bled to death slowly or quickly assassinated.
What he needs at his side, right now, is a mixture of consigliere, media manager, tactician, strategist, elder statesman and enforcer, and only one figure fits that varied bill. Mandy, ever the tribal loyalist, is up for it, as his reflections on a "sense of bereavement" at leaving the centre of political life make plain.
The downsides to recalling him, even in a nebulous backroom role, are immense. It would inflame that clanking pair of Balls to an incandescence that could melt diamond, render the "dignity in retirement" jibe childish posturing, ridicule Ed's ramblings about the "new generation", and unleash another avalanche of reflections on the Blair-Brown warfare and the Third Man's singular role in that.
However, Mr and Mrs Balls are quite combustible enough, thank you very much, as things are; the "dignity in retirement" remark was certainly childish posturing, of the kind leadership candidates happily repent once elected; the "new generation" was always cobblers (if Andy Burnham is a key member of that, it needs either heavy seasoning or scraping into the bin); and with the Ballses and Mili the Elder moving menacingly towards him from opposite directions, reflections on the Blair-Brown warfare aren't about to vanish. What summoning Mandy would do is superheat the noxious brew already bubbling away, and might even cauterize wounds that could become gangrenous if left untreated.
The other positives would be colossal. The public may not love Mandy, but they respect his intellect, trust his judgment, and know him as the last Labour superheavyweight in either House. He has handy experience of quashing coups against a vulnerable leader, while, as the aftermath of his meeting with Mr Osborne at Ms Rothschild's brother's Corfu home reminds us, he knows how to play with the Chancellor's head. He is indisputably a grownup, and in the primary school of fractious kids in which Little Ed is precariously head prefect, that is a priceless commodity. Besides, would you want him outside the tent pissing in?
At a definitive moment in political history, with the Coalition barely challenged as it sets about redefining the covenant between citizen and state in a manner unseen since the creation of welfare itself, the ship of opposition is steered solely by the undercurrents, its hopes of finding port resting on the Government hitting the rocks of economic turbulence and social unrest it may well avoid. In a sense, this is all fantasy politics. It would require a very big man, or a very desperate one, to swallow his pride and turn to someone he dismissed as a has-been a few months ago. Yet as Gordon Brown established when he unimaginably recalled Mandy from Brussels to save his hide, fantasy and reality can be interchangeable in the madhouse by the Thames.
If Little Ed isn't very big, he has compelling reason to be desperate. Six months after declaring his candidacy one fine May day, the moment comes to issue a Mayday distress call. Whether or not every Prime Minister needs a Willy, 21st century history teaches that every Labour leader requires a Mandy. High risk doesn't come close to hinting at the gamble in bringing him back - but far better to roll the dice now than go down with the ship, like Admiral Horatio D'Ascoygne in Kinds Hearts And Coronets, bravely saluting as the water laps over his face.