THE STORY SO FAR: Up against a pan-nationalist front, unionism was under-represented at the negotiations for the Good Friday Agreement: both the DUP and Robert McCartney's tiny UKUP party walked out over Sinn Fein involvement. During the last hectic night, Jeffrey Donaldson, David Trimble's right-hand man, left on a point of principle to do with prisoner releases.
Since then, not only has unionism been split over the agreement, but Trimble's UUP has been divided roughly 55 per cent - 45 per cent between those who back him and those who believe he's made too many concessions to republicans.
On 16 June he survived the tenth heave against his leadership; a week later the MPs Donaldson, David Burnside and Martin Smyth resigned the party whip and have now been suspended from the party. From ten Westminster seats in 1997, the UUP are down to three.
THIS really is the final showdown. It will not be pistols at dawn, but a disciplinary meeting on 17 July, followed almost certainly by a meeting of the Ulster Unionist Council which will end with Trimble or Donaldson being carried out feet first. Along the way, expect plenty of rhetorical fire and brimstone, conflicting advice from lawyers and trouble over parades, for the Orange Order - which these days has the political finesse of an intellectually-challenged tortoise after a heavy night - is lumbering into the row.
The theoretical bone of contention is the British/Irish Joint Declaration which the Donaldson faction failed to persuade the party to reject. There is much in the declaration that all unionists find offensive (freedom for on-the-run terrorists, dismantling of military bases despite the threat from dissident republicans, a body to monitor the agreement that includes a representative from the Irish government and so on). Yet it also contains an unprecedented detailed demand by both governments for the end to paramilitarism.
Trimble's objective is to use world opinion to force republicans to do what is necessary to get devolution up and running again: his tactics are to keep focusing on the failure of the IRA to disarm and say the war is over. If his opponents had got their way, the blame for the present stalemate would have moved back onto unionism.
What Trimble has going for him is clarity of vision. He knows that the majority of unionists would support the agreement if it brought them peace: a recent poll showed 76 per cent would share power with Sinn Fein if the IRA went out of business.
His challenge is to hold the nerve of his party while pressure stays on republicans. He would be the first to say that the agreement as it's been implemented isn't the agreement he signed up to: like the SDLP in private, he feels betrayed by the eagerness of both governments to sacrifice the political centre to the demands of the extremes. But he is above all a politician and a realist. He understands the weakness of the unionist hand and he plays it cleverly.
By contrast, his three opponents are muddled. Although there is nothing Donaldson wants more than to be First Minister of Northern Ireland, he is driven mainly by a sense of outrage. As UUP member Alex Kane put it, Donaldson lost the last UUC confrontation "because he had nothing new to offer. Yes, he spoke with passion - but he didn't seem to have realised that it was no longer enough to point out the flaws and failings of the existing process and institutions. If you want a change of policy and a change of direction, then it makes sense to let the audience have a glimpse of your road map." His bedfellows are dodgy. His mentor, Lord Molyneaux, Trimble's predecessor, has never forgiven the party's change of direction and style; Burnside, the most unpopular MP in the party, is driven by ambition and egotism; and Smyth is a bitter old man who has never got over being defeated for the leadership.
What the rebels have going for them is that while Trimble has been pounding the corridors of power in London and Washington and even Dublin, the grassroots of his party have become parched. UUP members know their leader has brains and courage but - rather as the British Labour party feel about Tony Blair - they don't think their leader loves them and they don't understand what he's thinking.
What Trimble really needs is a holiday, but he's not going to win this battle unless he tramps around the furthest corners of the province shaking hands and listening as well as spelling out his case in terms they can understand.
For now, the winners are republicans and the DUP - now suddenly the biggest unionist party in the commons. Licking their lips, they scream ever louder for an early election. If both groups weren't such puritans, champagne corks would be popping all over Northern Ireland.