It is a recollection that will not dissolve. I was peeing in a public urinal next to the most powerful British politician of the postwar period. In response to a benign inquiry about how he was faring, Tony Blair said: "Alastair has said I mustn't talk to you." This was a year before the 1997 general election, and his remark was intended in part as pissoir banter. But only in part. The then leader of Her Majesty's Opposition had been stung because some remarks he had made to me the previous day about income tax had become a slightly resonant story. And Alastair Campbell, the potent consigliere, had told him to keep stum in my presence. The incident says something about how much Blair defers to his close circle of advisers. It also says something about the cracks in his veneer of confidence. And before you ask, I did not look down and sideways.
I was musing on this when euro notes and coins were launched. Would the Prime Minister break the habits of a political lifetime and strike out, more or less on his own, on a campaign to take the UK into the European single currency?
Blair's modus operandi was summed up earliest and best by Paddy Ashdown, who spent an inordinate amount of time with him in the mid-1990s, vainly trying to put lead in his EU pencil. Blair is not a cowardly politician, but nor is he especially courageous. Ashdown's astute analysis was that Blair waits for a majority view to form and then announces - after the event - that he is the leader of the majority.
This is not the same as backing away from a conflict. When kickings had to be delivered, to the trade unions and old left, Blair was not squeamish. But when has he ever picked a fight that he was not certain to win? And the whole point of working with Philip Gould and Campbell was always to be in step with public opinion.
So here are the horns of Blair's euro dilemma. His role in history is to make the UK a respected elder within the EU, rather than a pipsqueak troublemaker. And although he has done much to restore our European credentials, the UK will still be seen in Frankfurt and Paris primarily as an agent provocateur, unless and until we sign up for monetary union.
Whether or not this is a respectable reason for wanting to join (I think it is), it has little sway with voters. The enormous, unmissable fact is that public opinion is against him, although the degree of visceral opposition to the euro should not be exaggerated.
Business people and ministers are persuaded that the advent of notes and coins will somehow seduce the British electorate. Quite why purchasing lager on the Costa Brava with the new faux-bronze coins should make any difference is beyond me. In fact, I would argue that public attitudes may harden against the euro.
Familiarity with the currency will bring home some tough realities, such as the great cost and inconvenience of re-equipping a substantial economy with the new currency units. Will most people see this as a price worth paying for the convenience of avoiding the bureaux de change once a year? Possibly, but I would not stake a government's reputation on it.
It is these conflicting pressures - between Blair's big political ambition and the methods on which he has constructed a career - that make me feel 2002 will be the decisive year for the UK and the euro, even though his de facto deadline for whether to hold a referendum is mid-2003. If 2002 is another year of tepid government support for the euro and conflicting signals from the adjacent houses in Downing Street, I'd bet on membership being deferred until after the next election.
There is another, non-trivial obstacle in the way of a pro-euro offensive, which is that the basis for an effective campaign has yet to be constructed. Blair's best hope is an overwhelming endorsement of euro membership from Gordon Brown. The Treasury would need to fix his five economic tests so that the threat to jobs, investment and UK prosperity posed by keeping the pound would appear unambiguous, outweighing the political sacrifice of transferring more power to Brussels. And the coup de theatre would be a sloughing off of all doubts about the euro adventure by a chancellor who has assiduously groomed a sceptical image.
Such an ostensible Damascene conversion is possible, partly because Brown's opposition to monetary union is wildly exaggerated. And I will not bore you again with my views on the connection between Brown's euro posturing and his determination that Blair should not rat on an understanding to hand over the keys to No 10 before those fine locks of his look implausibly black.
But even with Brown's backing, a decision to go for the euro would take all Blair's courage, a quality he told the adoring throng at last year's Labour conference that he hoped he would manifest. I hope so, too - which is why I am desperately trying to suppress all memory of l'incident du pissoir.