As Ulster Unionism threatens to implode and place both itself and the Belfast Agreement in the dustbin of history, one vital question is overdue for serious discussion. Where is the British government in all of this? This crisis is nothing if not predictable. The probability of David Burnside's defeat in South Antrim was acknowledged by all serious commentators in early September. It provided the new element which gave credibility to Jeffrey Donaldson's challenge to the Ulster Unionists' policy direction - the fear of electoral meltdown for the party.
That fear may well be exaggerated; on the higher turnout of the general election, a seat like South Antrim should return to the Ulster Unionist fold.
Polls suggest that David Trimble has a respect across both sections of the community which no other Ulster Unionist politician can challenge. But the fear of meltdown is there, particularly for those local councillors who face the prospect of local elections next May. By definition, a novel conjuncture requires a novel response, but response from London came there none.
It is true that Peter Mandelson is apparently set to deliver to Mr Trimble's agenda on the flying of flags on government buildings and the RUC name on the title deeds of the new police force.
But all this arises from a dialogue begun very intelligently by Mr Mandelson earlier in the year and is unrelated to the present crisis, except in so far as their delivery now, it is hoped, will calm nerves in the Trimble camp.
Making all allowances for the heavy objective constraints of the situation, this has certainly not been the most gloriously proactive phase in the history of the Northern Ireland Office. It has been remarkably passive as the crisis worsened.
Eloquent only in providing reasons why something cannot be done to help - even in those rare areas where there is an SDLP and Ulster Unionist commonality of interest - the NIO has made only one new intervention of note, and that an error of judgment.
This was Peter Mandelson's perceived flirtation (in an interview with Ken Reid of UTV) with the threat of joint authority. I say perceived because Mr Mandelson is too shrewd a politician to use the actual words. Designed to help David Trimble, it backfired badly.
Far from frightening unionists, it merely insulted them with a display of British bad faith.
It probably also strengthened the resolve of those republicans who think that Gerry Adams is in danger of surrendering too much ground. Why move on the arms issue if by not moving, one will be rewarded by joint authority? Let us not forget that was Mr Adams's original objective when he launched his side of the peace process in the early 1990s.
For good measure, Mr Mandelson's intervention was less than enthusiastically received by Irish officials, who might reasonably have asked themselves, who was being insensitive to unionist feelings now?
Yet, when this passivity received its inevitable reward - a move within the Unionist party to close ranks around a compromise motion which would likely impose impossible deadlines on the process - the London reaction was one of surprise and, understandably, concern.
Nobody believes that the republican movement with its current difficulties in west Belfast will react sympathetically to any Ulster Unionist move away from the May deal which set up the Executive - a deal endorsed narrowly by the Ulster Unionist Council earlier this year.
More importantly, a unilateral breaking of the terms of the understanding of May gives the republican movement the high ground - a high ground which it visibly lacked at the time of the February suspension when it was the republican movement which was widely perceived to have reneged unilaterally on an understanding.
Mr Trimble has, as he repeated endlessly in recent days, a bottom line on decommissioning. But he wishes to be left in control of the timing of that agenda because timing is the clue to winning the inevitable conflict with the republican movement, which will not want to go beyond the arms inspections already granted.
The IRA's confirmation yesterday that it will allow a further arms dump inspection at a date to be specified may be dismissed by the Donaldson faction as an empty, cynical public relations gesture. Maybe so, but the reality is that no IRA member will ever use these dumps again.
The new inspection will allow the process to be seen as a real one. It is one of the many worries of the present crisis that the inspections process has been so rubbished in recent weeks that the inspections currently work for Jeffrey Donaldson's cause and not David Trimble's. This is an absurdity and any new inspection would provide the perfect moment to exhibit the serious nature of the process.
We are in for a dramatic 72 hours. Today's visit by Tony Blair will at least serve to remind Ulster Unionist Council delegates that the perceived realities in Antrim, Carrickfergus and Larne are not the only realities which count; a unionist by definition has to be concerned with the realities in London.
But there is a point to be made on the other side. The fatwa against the anti-agreement unionists has been the greatest error of government policy against the referendum. A constituency - many of whom were seized by genuine moral doubt - was treated as if it comprised unrepentant bigots who could be marginalised.
It is time for some mending of fences. Machiavelli argues in The Prince that a powerful leader can easily afford to break his pledges. But Machiavelli also argued that this could only be done when the circumstances which caused these promises to be given no longer applied.
In the case of Northern Ireland, the circumstances which caused Mr Blair at the time of the reform to articulate so brilliantly a vision of a political future free from the threat of violence still apply - even more sharply now than they did in 1998.
The timing of this debate does not suit Mr Trimble. An extra week would have allowed a fuller public debate.
But the delegates should remember one thing: they have a stark alternative. Either implode or play it long and place the real problem of the process back at the door of the two governments and the republican movement, as they did between November 1999 and February 2000.
Joint authority is not just around the corner, but a bleak political future is. This is a future in which unionists cease to make history and allow it to be made by other forces and traditions - forces and traditions which have no reason to hold unionist concerns at heart.
Paul Bew is Professor of Irish Politics at Queen's University Belfast.
