`We have done our bit. Mr Adams, it's over to you. We've jumped, you follow." With those words last November Mr David Trimble hoisted himself on to the "high moral ground" of Northern Ireland politics.
Hard-nosed politician that he is, he can hardly have thought to enjoy sole occupancy for long. "On the back foot" is not a position in which Sinn Fein likes to languish.
The Irish and British governments saluted Mr Trimble for his courage in forming the power-sharing Executive with Sinn Fein without so much as an IRA commitment to decommissioning.
And on February 11th, the republicans having failed to deliver, Mr Mandelson did what he had promised, and suspended the Executive.
By that point, however, it had already become clear that Mr Ahern's brave rhetoric was just that. Faced with republican intransigence, the Irish Government appeared effectively to fold its position on decommissioning as a requirement for participation in government for more than a short transitional period.
Within the week it was plain, too, that the British Secretary of State was in regretful mood.
Unionist alarm bells might have begun ringing when Mr Mandelson described the post-suspension situation as "a Mexican standoff"; the direct linkage of devolution and decommissioning the possible guarantor than neither would be achieved.
This tetchy characterisation of both sides clinging to their principled positions carried the clear implication that each would have to move if the stalemate was to be broken.
However, the Ulster Unionists appeared untroubled by this, or by Mr Mandelson's rewriting of the history of last November.
That direct linkage, after all, had been the foundation of the Blair-Trimble contract with the unionist electorate in 1998, and the whole basis of Mr Mandelson's decision to suspend.
Moreover, the linkage had delivered one half of the purported bargain, devolution.
Before and after St Patrick's Day in Washington it has become ever more apparent that Mr Mandelson was no decommissioning junkie.
On April 10th the Irish News reported his assertion that an unmistakable signal of the IRA's peaceful intent would be worth much more than a token gesture on arms.
"Decommissioning is essential and has to be addressed. The question is how. I believe that we must think twice before linking decommissioning directly to the continuance of the institutions," he said.
In his subsequent interview with The Irish Times before Easter, Mr Trimble proved resistant to questioning on the Mandelson position; insisting he did not regard the Secretary of State's comments as a statement of British government policy, and that no change in policy had been conveyed to him.
There might be an obvious strategic calculation in Mr Trimble's adherence to that position, even if he privately feared otherwise.
Nor should it be assumed he was simply being disingenuous. Some of Mr Trimble's closest advisers acknowledge that London would happily see the arms issue settled and dispensed with on other than unionist terms.
At the same time they evince considerable confidence that, in the end, Mr Blair will not break with Mr Trimble over any new deal he feels unable to sell to the Ulster Unionist Council.
If that assurance is cast-iron, then the latest round of prime ministerial diplomacy, which Mr Blair hopes will resume at Hillsborough this evening, can easily come to naught.
In his Irish Times interview in the same series, Mr Gerry Adams said his huge mistake last time had been in attempting to deal with the weapons issue on unionist terms.
The implication of that seemed obvious.
The expected push is compelled by the knowledge, in London, Dublin and Belfast, that May 22nd is the psychological breakpoint. And the suspicion that London will be prepared to put the squeeze on Mr Trimble one more time is increased by the internal logic of the peace process.
Whatever the detail of the present negotiation, one bet seems certain: the two governments are not going to give up on the agreement, or regretfully conclude there is no prospect of confidence sufficient to enable the resumption of devolution.
Were London to do so unilaterally, the crisis in Anglo-Irish relations would be profound. Dublin opposed the February suspension, and manifestly does not consider the republican movement in "default".
Mr Mandelson, moreover, has made it clear that, while expecting decommissioning to happen over time, his immediate need is that republicans make plain their intentions over arms, and provide confidence "that democracy not violence will drive politics in Northern Ireland now and for all time."
SHOULD the republicans prove half-obliging, it seems inevitable that London would press for one further dilution of Mr Trimble's "no guns, no government" policy.
And some close observers of that scene appear confident that Mr Adams and Mr McGuinness might just be about to deliver some advance on the IRA's February 11th statement to Gen. de Chastelain.
In the immediate aftermath of suspension, some senior British sources privately indicated their belief that that statement did mark a significant shift in republican thinking.
Intriguingly at the time, Mr Seamus Mallon suggested the general had fuller knowledge of the IRA position than was publicly revealed. Mr Mandelson's public comments suggest that, for him, the vital missing component was a commitment to see weapons put permanently beyond use.
And while some unionists will reject the resumption of devolution on the basis of anything less than "product", there is no doubt that a statement of such intent could be intended to provide the long-awaited confirmation that the IRA's war is over.
But when? In what context? Over what time-scale? Subject to what form of verification? And by whom?
If Mr Trimble is to persuade the Ulster Unionist Council to jump with him, these are the questions to which some of his strongest supporters will be demanding answers. As ever, in the detail resides the devil.