To the victor the spoils. That certainly is the Ulster Unionist leadership's intended outcome for next week's all-important meeting of the Stormont Assembly. And if David Trimble does emerge once more First Minister of Northern Ireland it will be a political coup without compare.

It is not unknown for politicians to quit office on grounds of high principle. However, assorted academics have struggled this week to think of a previous occasion when a leader has done so expecting and demanding re-election and had his wish fulfilled.

"He's the old Napoleon General, isn't he? Lucky," observes one admiring colleague. And if luck is one of the factors that make otherwise ordinary men dominant and successful leaders of their times then David Trimble has had plenty of it. Yet others insist there is more to the Trimble phenomenon than mere chance and good fortune.

"They can say what they like, but there is a certain stardust, a bit of glamour about the man," offers another by-no-means uncritical observer. "You certainly can't deny his courage or his stamina. He's had to take an awful lot of crap, it's been low down and dirty. And, of course, he nearly wrecked his party in the process. That leadership challenge by Martin Smyth would have seen-off any mainland leader. But look at him. He persisted and he actually faced the Provos down."

Others are not so generous. On Monday Gerry Adams took a pre-emptive swipe at the naysayers who would question the detail of the IRA move to put weapons beyond use rather than seize the opportunity for "a liberating leap" toward the full implementation of the Belfast Agreement. And he may have been relieved 24 hours later at the lack of triumphalism attending Mr Trimble's sober declaration: "This is the day we were told would never happen. This is the day we were told we would never see." The Ulster Unionist leader, however, may have felt there was nothing the Sinn FΘin president could tell him about begrudgery.

Peter Robinson, the deputy leader of the DUP, allowed that Osama bin Laden may have had something to do with republican calculations, but contemptuously dismissed the suggestion that here was vindication for the Ulster Unionist leader. Having "appeased" republicans for three years, he suggested, Mr Trimble had finally won an IRA "gesture" after just three weeks "following the tactics of the DUP".

To Ulster Unionist and most other ears that charge will ring distinctly hollow. Michael McGimpsey mocked the DUP's re-appointment of Ministers Robinson and Dodds as the latest example of a DUP willingness to "piggy back" on a process from which they cheerfully extract "the gain" while the Ulster Unionists "take the pain." And there was much merriment in Mr Trimble's office yesterday over a newspaper cartoon depicting self-confident Ulster Unionist ministers returning to Stormont trailed by DUP ministers, tongues hanging out, being brought to "heel".

There is, of course, no necessary contradiction between the DUP's decision to take-up its ministerial posts (they would otherwise be re-distributed to other parties) and the party's determination to prevent the election of First and Deputy First Ministers and thus force a re-negotiation of the Belfast Agreement.

Moreover there is a dangerous tendency - never more pronounced than at moments of "historic breakthrough" in the peace process - to disregard the renewed strength and potency of a DUP mandate, the importance of which at least was acknowledged by the Northern Ireland Secretary, Dr John Reid, in the Commons on Wednesday.

Enthusiasts for the Agreement may recoil from the spectre of Paisley-as-vulgarian, now openly questioning the veracity of General de Chastelain and the Independent International Decommissioning Commission. Only a fool, however, will deny that his words will find a resonance in many unionist and loyalist heartlands across Northern Ireland. The words on the placard were meant to spell defiance: "Ardoyne accepts the IRA's surrender." But the mood there and elsewhere in the pro-Union constituency remains sullen and resentful, and the hopes engendered by this week's "ground-breaking" IRA initiative battle against a widespread scepticism fuelled by a three-year wait for the beginning of a process Prime Minister Blair told them would begin immediately after the Assembly elections in 1998.

Inside the Trimble camp, there is acknowledgement of underlying unease - a desire on the part of some to be persuaded tempered by the General's inability to say where the IRA event took place, precisely what weapons were put beyond use and whether, indeed, this is "the start of a process" leading to total disarmament.

Even if the DUP fails to block Mr Trimble's return to office next Friday, the leading Ulster Unionist dissident Jeffrey Donaldson has served notice that the war of attrition will go on - insisting that the party's re-entry into government with Sinn FΘin should not be "unconditional". He is another man claiming some vindication this week, and with arguably greater cause than some leading Trimble loyalists who themselves doubted, and privately opposed, the resignations strategum designed to force the republican hand.

Mr Donaldson was in Singapore on Tuesday night en route to Australia, awaiting a read-out from Mr Trimble's meeting with General de Chastelain. The subsequent signal was that the Lagan Valley was not spoiling for a fight. And the leadership will be hoping his "conditional" approach to the IRA move will serve as a green light for the North Down Assembly Member Peter Weir to get in-line behind Mr Trimble, at least for now.

It is the measure of Mr Trimble's internal difficulties, however, that he raised with Mr Blair on Wednesday the question of "sanctions" to be deployed against any paramilitary organisation failing to complete the disarmament process by next February, when the remit of the IIDC is scheduled to expire. The implication of Mr Trimble's intervention during question time in the Commons was that the Ulster Unionists could do again what they had done before.

Downing Street will be hoping this pose is a matter of party management ahead of today's UUP Executive meeting in Belfast. As Number 10 is hopeful unionists of every stripe will weigh the consequences of bringing the process to another shuddering halt.

Beyond the sceptical ranks of Ulster's unionists, too, there is a readiness to question Mr Trimble's part in this week's unprecedented development within the republican movement. Not even a movement that Mr Adams maintains does not respond to pressure can have been impervious to the events of September 11th. Even before then, most observers believe the misadventures of three republicans in Colombia had changed the equation and brought the republican movement under ferocious American pressure.

That argument may rage-on.

To key Whitehall insiders, however, it is largely beside-the-point. As one source puts it: "There may have been many times when we would have wished he would do things differently, express himself differently. But nobody has the right to criticise him for his method of walking a tightrope nobody else with credibility could have walked. This process has depended on David Trimble. And it was the lack of an alternative to him which forced nationalists and the two governments, and in the end the Republican movement, to see that, for unionists, decommissioning was the issue that had to be dealt with."

That view is echoed by an Assembly colleague, who says: "You can argue about how the various pressure points came together. But I don't think the Provos would ever have moved if there hadn't been a political process to engage with. And Trimble kept the process going."

That view was reflected, too, by Mr Blair and Dr Reid earlier this week, when they praised Trimble's perseverance and his determined stand against the politics of isolation.

Lavish praise from Downing Street only serves to further damn Mr Trimble in the eyes of Dr Paisley. To the Big Man, the Ulster Unionist leader is Terence O'Neill re-incarnate, a latter-day "sell-out" merchant.

In the pantheon of unionist leaders, of course, the comparison Mr Trimble prefers is with Sir James Craig. He has certainly lived through similarly dangerous times. Craig was prepared to meet Collins and de Valera, and to cut deals, knowing all the while that the British were prepared to pull the rug from under him.

Likewise, Trimble is seen by some historians of his era as the Unionist leader who, perfectly understanding that London was unreliable, consciously and deliberately sought security for Ulster's unionist cause by putting himself on the side of the British state's own peace faction.

Having secured the principle of consent and the abandonment of the Republic's territorial claim to Northern Ireland, the British state now hopes Mr Trimble's fellow Ulstermen will not think they can emulate Sinn FΘin, and stand themselves alone.