There is a curious atmosphere in the Northern Ireland Assembly. One the one hand, the fixtures and trappings of a permanent parliamentary home are being put in place. The latest innovation is a post office, with the full range of services, including parcel post, national savings bank, passport services and "bureau de change - 24 hours notice required".
At the same time there is an air of uncertainty and impermanence, of doubt about the future and a feeling that the carefully built structure could collapse over the "D" word.
All the talk in the corridors was about Bertie Ahern's carefully calculated weekend intervention on decommissioning. Gerry Adams tried to put it behind him by calling it yesterday's news, but privately there was a mixture of gloom, concern and puzzlement in the republican camp.
Unionists were, naturally, more upbeat. Asked if they were pleased with the Taoiseach's comments, senior unionists grinned and one of them said: "Absolutely - he's a great guy." It's not every day top unionists praise a Fianna Fail taoiseach in such terms.
Pressed on whether senior unionists had intimated to the Taoiseach that a bit of tough talking on decommissioning would be helpful at this time, UUP sources responded coyly that they "couldn't possibly comment".
UUP sources, however, said they would not be surprised if the Taoiseach made a countervailing verbal gesture towards nationalists in the near future - in fact he had already begun to retreat from his initial stance.
Senior unionists characterised the Taoiseach's comments as "time-specific" and Mr Ahern's words undoubtedly helped shore up David Trimble's position in the UUP and assisted his efforts to keep the party united.
While Mr Peter Weir reiterated his intention to oppose the leadership line in today's vote, some senior party figures had not entirely given up hope that Mr Roy Beggs jnr might change his mind and support Mr Trimble in the end.
UUP insiders said considerable effort had been put into persuading Mr Beggs to see the "one true path". The leadership line with dissidents has been to say, in effect: "We are holding the line on decommissioning and we are not going to sell out, so why not support us?"
Meanwhile, Dr Mo Mowlam, attending a function at Holywood, Co Down, was asked by reporters for her comments on the Ahern interview and responded in bemused terms as if she hardly knew what the media were talking about.
There was a sideshow at the Assembly involving Mr Peter Robinson of the DUP and Mr Martin McGuinness of Sinn Fein, with charge and counter-charge about involvement with the extra-parliamentary side of Ulster politics.
The most powerful speech of the day came from Mr David Ervine, recalling meetings he had had with people as a representative of the Ulster Volunteer Force. Mr Ervine hinted there was more to come on the subject if people wanted to go down that road. Nobody took up the invitation.
However, the real business of the day was debating the report from Mr Trimble and Mr Mallon on new government departments and North-South bodies.
The First Minister complained that a "turf war" and the obduracy of some officials were hindering progress. It was a rare hint of real politics in a rather abstract debate. Indeed, some of the concerns of civil servants have already been expressed in the news paper of the Northern Ireland Public Service Alliance.
While the union stressed its anxiety to facilitate new arrangements, this would have to be done without harming the "pay, conditions and expectations" of its members.
The union welcomed the prospect of the dispersal of civil service jobs to other parts of Northern Ireland, because they were at present concentrated to an excessive degree in and around Stormont. It has already emerged, for example, that the headquarters of the North-South ministerial council will, initially at least, be in Armagh city.
On a broader front, the UUP has cleverly focused attention, not on this week's debate, but on March 10th, known as the "appointed day" for devolution. In this way, it has nipped in the bud any attempt by its opponents to create fear and anxiety in the unionist community over the weighty matters being decided today.
Though anti-agreement unionists are right in their assessment that today's vote has historic implications, for good or ill the die will be cast and Northern Ireland's future to some extent will be placed in the hands of the Secretary of State.
She will have to decide when she provides the speaker of the Assembly with the standing order that will allow him to invite nominations to the executive. The No camp in unionism argues that the pressure to seat Sinn Fein at the cabinet table will be irresistible.
It would be ironic, although rather unlikely, if Bertie Ahern proved to be the last bulwark against this eventuality.
Meanwhile, Sinn Fein has called a day of protest rallies in Belfast for February 28th to call for "the implementation of the agreement", by which it means cabinet seats without decommissioning. The arm-wrestling is set to continue while, all the time, the marching season comes closer. Attention is already focusing on the Orange Order parade set for April 5th on Belfast's Ormeau Road, a flashpoint in previous years. That will be only five days away from the first anniversary of the agreement.
The psychological pressure on parties to overcome the decommissioning impasse and get on with carrying out the wishes of the people is intensifying every day.