Sinn Fein's negotiating strategy in the last week of the Stormont talks was a carbon copy of the tactics which led to the production of the "original" Mitchell document in April 1998 which was so unacceptable to Unionists: hints of amazing Sinn Fein moderation and dilution of republican principles were traded for intergovernmental support for the production of a document which would put pressure on Unionists. Although, second time around, David Trimble cannot have been surprised by such a development, the air was again thick with rumours and obvious indications of the two governments' mentality, but he was inhibited by his party's divisions.

As a consequence, right up to and even past Mr Blair's midweek deadline, the Ulster Unionist negotiating strategy was conservative and passive; almost as if the Unionists believed the governments would see through their own propaganda.

Understandably so. There was no money on the table, no report from Gen de Chastelain, simply an impression assiduously created by the two governments that the Sinn Fein position on decommissioning had radically shifted. The Unionists, on the other hand, found in their dialogue with Sinn Fein the traditional claim that there was no certainty about decommissioning.

As the government's media spin went even more wildly and dangerously out of control as the deadline approached, the entire process almost crashed there and then as the officials prepared for the end.

A substantial part of the Unionist Assembly team seemed to want an immediate exit; David Trimble, for his part, argued for a strategy of continued engagement and negotiation. Papers were produced in the early hours of Thursday morning, the very act of doing so preserved the wilting Belfast Agreement, allowing it the very temporary shelf-life it now enjoys.

As leaked documents have now made clear, at least some of the advice Trimble had earlier received had pointed up the advantages as well as the disadvantages of Mr Blair's new approach for Unionists.

Mr Blair's attitude to his pledges of last year is not properly understood: he has not simply walked away from them. He is engaged upon a dramatic game of "double or quits" designed to vindicate them. Essentially, he said then that the republican movement must make the decisive break with its violent history and structures in order to take part in government.

What was understood as a precondition, that the republicans have a clean bill of health on the matter of such peccadilloes as murder, beating and bombing, is no longer a precondition but rather an objective of their installation in government which, if not rapidly followed by the act of decommissioning, ends the whole experiment by legislative sanction.

It is a dramatic gamble and all the talk about "seismic shift" is designed to obscure the fact that there is no guarantee of success.

TO a frightening degree, the British and Irish governments are dependent on the undertakings intimated in private by a few key leaders of the republican movement; public declarations so far remain elusive, though it must be conceded that Gerry Adams, at least, has radically broken with the mantra of "no, nothing, never", as he contemplates the political expansion of Sinn Fein, North and South.

Later on Thursday, Mr Blair addressed the Ulster Unionist Assembly meeting. Initially presented as a success, the meeting turned out to be a disaster. At its core was Mr Blair's apparent offer to exclude Sinn Fein if it did not decommission. This went down well, but when it emerged, as it inevitably did on Friday, that this was an imprecise use of language because the whole executive was to be collapsed, there was an inevitable outburst of Unionist fury.

The Prime Minister clearly ought not to have used potentially misleading language. His advisers, after all, were well aware of the importance of openness and honesty in dealing with the Assembly party. Instead, the impression is left that he exploited the politeness and deference of his audience.

At the same time, it is a comment on the naivety of the Assembly party that they did not appear to have read Mr Blair's Times article of the previous week, or known what has been a commonplace of political gossip in Belfast for weeks, that Tony Blair, originally a supporter of the exclusion model himself, had not been able to get the necessary backup from Dublin and the SDLP. Nevertheless, the proposed suspension, unsatisfactory though it is from a Unionist point of view, should not be seen as a collapse, rather more as the placing of the institutions on ice while new ways forward are considered.

But what new ways? What is the appreciable difference between suspension in July or in September? Here the British government's faith is the key issue. Today, London claims that if the project collapses on the failure of decommissioning to take place, Unionists will have the high moral ground.

However, while the Unionists may have the high moral ground, will the republican paramilitaries still enjoy the inside track? A deal which broke down over the failure of decommissioning would restore the status quo (back to square one), says Mr Blair. But this status quo is one in which the all-pervading anxiety of the two governments appears to be to avoid the possibility of a breakdown in the IRA ceasefire.

There is, as yet, no guarantee that this might prove more efficacious politically than the high moral ground; a high moral ground which, some might argue, is already occupied by Unionists on decommissioning.

AS an exercise in "rational choice" theory, it is being presented as a very simple one. Either accept the defeat and humiliation today of being the party which brought down the Good Friday agreement and prevented, so the world appears to believe, IRA decommissioning; or go through the pain barrier, set up the executive and see the wondrous act of decommissioning commence; or, alternatively, see the executive collapse, with Sinn Fein to blame.

At this level there is only one option. Most people prefer the probability of victory or the possibility of a draw to the certainty of defeat.

But this leaves out the matter of communal pride. Unionists bitterly resent the pressure on them to facilitate the promised final transformation of gunmen into politicians. The imposition of a deadline alone had hardened opinion dramatically.

Even more incomprehensible is the two governments' apparent willingness to demand David Trimble change party policy on so sensitive an issue, yet to abandon him without means of retreat. Quite rightly, David Trimble will not roll over and play dead for the two governments, but the astonishing failure of political understanding which put him in that position has succeeded in arousing the deepest misgivings among pro-Agreement Unionists.

Then there is the not unimportant matter of morality. The moral precepts the Ulster Unionists were raised with do not include the Maoist concept, "Political power grows out of the barrel of a gun", so well internalised by the two governments that they can proclaim this squalid negotiation circus as a triumph for Irish democracy.

Throughout the entire negotiation, the Ulster Unionists spoke as the representatives of moral principle in politics. They found it difficult to grasp the political reality: the republicans had guns, they had not, and the government wanted peace from a movement that has been showing ugly signs of returning to war.

The British government, in particular, acts as though it believes that the IRA has one remaining potential casus belli, non-inclusion in the governmental arrangements envisaged in the Good Friday agreement and that it is determined to remove this, at almost any price.

Worse still, the failure to negotiate the Good Friday agreement would have been shrugged off by the Protestant community, as hardly surprising, but having stretched itself to such a compromise it now feels affronted by a policy it sees as appeasement of terror. Appeasement of terror is indeed the only game in town, but it should not be forgotten that appeasement might work, and has worked so far. Sinn Fein's hints of moderation last year led to the acceptance of the new Stormont and the dropping of the Republic's territorial claim on the North. This year's hints may lead to decommissioning and, if not, a major political setback for the republican movement.

"Rational choice" theory indicates moving to devolution, but communal pride and mistrust of Mr Blair rather suggest that the prospect may be delayed with no guarantee of eventual fulfilment. But it is up to Mr Blair. All this talk of Unionist "blame" obscures the British government's vulnerability. If the ceasefire breaks down, mainstream British public opinion (worryingly considerably less comfortable with the current Irish policy than the Parliamentary Labour Party) will blame Mr Blair for releasing prisoners on a false premise. Mr Blair has every incentive to dig deep.

Paul Bew is professor of Irish politics at Queen's University Belfast