This meeting was a defining moment for unionism, writes Gerry Moriarty, Northern Editor.
Analysis: Jeffrey Donaldson described last night's Ulster Unionist Council as a "defining moment" for Ulster Unionism. It was also a defining moment for Mr Donaldson, a brief moment to savour for Mr David Trimble before his next challenge.
There are always challenges for Mr Trimble but after last night the so-called men in grey suits could hardly have reason for suggesting he fall on his sword.
We've now had a dozen such defining UUC moments, twelve times when David Trimble had to slug it out with the anti-Belfast Agreement wing of the party since the 1998 Good Friday deal.
On all previous occasions matters remained ill-defined afterwards - a once proud party in a hopeless mess, muddled and divided.
The party spoke with two voices, those of David Trimble and Jeffrey Donaldson. Uno duce, una voce, was what Mr Trimble sought but could never achieve.
This time though Mr Donaldson may just be right. Last night's vote in favour of Mr Trimble should be a defining moment. Quite what happens next may take a few days, maybe even a little longer, to sort out. But it seems there is about to be a parting of the ways. The divorce papers should be signed shortly.
It could be a bitter separation, judging by the mood in the Ramada Hotel in south Belfast last night. The UUC meeting was scheduled to begin at 7 p.m. but the delegates were arriving from 4 p.m. About 900 were entitled to attend and over 800 turned up, which for a sunny Monday in June is a huge attendance.
Delegates knew what was at stake. There was much talk of the Joint Declaration, of the Royal Irish Regiment, of whether or not Dublin would have a role in the Assembly through the sanctions body, the International Monitoring Body. All important to unionists, but secondary. Last night was about who led the Ulster Unionist Party, David or Jeffrey?
The atmosphere was charged and nervous. This was the battle that was promised at numerous other UUC showdowns but the battle that was never properly fought.
It was last night. Belfast councillor Mr Jim Rodgers tried for middle ground. He proposed a half-hour adjournment mid-way through and wondered could the disputing sides not work it out. He was howled down. There were compromises in the past but last night there was no quarter.
Mr Donaldson is, as he said, considering his position. That is accepted shorthand for quitting the party. To do anything less would be abject.
Those on his side of the argument such as the Arlene Fosters, the Rev Martin Smyths and the David Burnsides of the UUP must consider their positions as well.
Ms Foster may consider there is no point staying in a party whose leader she virtually holds in contempt.
She could follow Mr Donaldson. Mr Burnside wants Mr Trimble out but has said he will remain in the party. Mr Smyth is with Jeffrey but that doesn't necessarily mean he would break his long-standing political and emotional links with the UUP.
Many other like-minded Ulster Unionists face hard choices in the days ahead.
If they travel with Mr Donaldson where is he going to take them? Into the DUP, a new party, or the political wilderness? Even for some doctrinaire anti-agreement Ulster Unionists joining the DUP would be a step too far. It might even be too far for Mr Donaldson.
Mr Donaldson could set up his own party, or reach a coalition-type accommodation with the Rev Ian Paisley and Mr Peter Robinson.
He could even take the DUP whip at Westminster, which would make the DUP rather than the UUP the fourth largest party in the House of Commons. Embarrassing for Mr Trimble, but at least there is the plus of having Mr Donaldson out of his hair.
This latest blood-letting shakes the Belfast Agreement. But with devolution suspended and elections postponed it is pretty shook already.
This victory for the pro-agreement bloc of the UUP offers some hope of resurrection. From a unionist perspective it places the spotlight back on republicans.
With this result we also have Mr Trimble a little more secure in his leadership, although such is the dysfunctionality of the Ulster Unionist Party you are never quite sure what booby-traps lie ahead.
Still, the Ulster Unionist leader should have slept well last night.