He was at the time riding on the crest of a wave, busily harvesting concessions from a Conservative government desperate to keep his goodwill. But today he is on the horns of a difficult dilemma, having discovered that Labour, the republican movement and the Irish government have all proved capable of playing a much longer game than he had envisaged.
Neither London nor Dublin has accepted his characterisation of the republican movement as something which "has to be smashed". Instead they are about to bring Sinn Fein to the table, leaving him to make the most important decision of his life: whether to join them or walk away.
It will be a knife-edge decision. Mr Trimble has spent his career on the right of Unionism: a Tory minister once famously said that he "nearly puked up my Frosties" on hearing the Unionist leader described as a moderate. When elected leader of the Ulster Unionist party two years ago he was the most hard-line of the five candidates.
Yet as an intelligent and comparatively young man he has also displayed modernising instincts. Keenly aware of the need to project a better image for Unionism, he will be aware that a boycott of talks would be both a political and public relations disaster.
His election followed "Drumcree I", the 1995 Portadown marching controversy in which he was noted for his uncompromising stand. This, his Upper Bann constituency, was the birthplace of Orangeism and remains its heartland; its MP is therefore required to be staunch in defence of the Orange cause.
When he became an MP in 1990 he was already an Orangeman of long standing as well as a figure identified firmly with the right. His early career had in fact been one of opposition to the Ulster Unionist party on the grounds that it was too soft and prone to compromise.
By 1978, however, he had quietly joined its ranks, though it was not until the 1990s that his career took off at a pace which in Unionist terms could only be described as meteoric. Those who had hoped, perhaps fancifully, that he would become a De Klerk figure have so far been disappointed as he has if anything aligned Unionism even more closely with Orangeism.
One of his biggest problems is that Unionism and Orangeism are both now possibly more internally divided than ever before. Two years on, his leadership is still in its infancy, but even within that period the divisions and confusions have widened considerably.
In other words he has been unable to find and raise a Unionist standard to rally the troops and end the splintering in the ranks. There are so many factions and divisions of opinion, in fact, that it is impossible to say whether a majority of Protestants and Unionists would wish him to leave the talks or stay in them.
Most of the activists in his party seem strongly wedded to the idea that arms decommissioning must be guaranteed before the party shares a table with Sinn Fein. This is also the strong position of his chief rivals for Unionist votes, the Rev Ian Paisley and Robert McCartney.
But the position is very different elsewhere in the Unionist spectrum. Senior figures in the business community favour the idea of talking, guns or no guns. So too do the fringe loyalist parties, who have a certain empathy with the IRA position: their loyalist paramilitary associates have themselves made it clear they will not be handing over any weapons. Some senior Protestant clergymen are also against the idea of a walkout.
Mr Trimble is also presumably aware that he has dangerous enemies within the top ranks of his own party and they will be eager to capitalise on any false move he makes. One of these was memorably described by a close observer: "He's as intent on destabilising from the inside as Paisley and company are from the outside. He just sits at the back like a big pasha, doesn't intervene but watches for the main chance."
The dilemma is an acute one. If Mr Trimble stays in the talks and cannot survive the inevitable criticism his leadership could be destroyed. But if he exits he could leave his party stranded on the outside while the peace train moves on without it. It is thus a moment of definition both for his party and for Unionism as a whole.Reuse content