The refusal of the IRA to decommission has reinforced traditional unionist fears that the Provisionals were never serious about the peace process and are planning a return to war.
In the current circumstances these fears are wholly understandable, but according to informed sources they are wrong. A majority of the IRA Army Council supports the political direction of the Sinn Fein leadership and wants the new Assembly and Executive to work.
The reason the Provisional IRA is not decommissioning is to prevent a split in its ranks. Sources estimate that at least a third of its members would leave if arms were handed over. Many would join the so-called "Real IRA".
Although "Real IRA" guns have been silent since the Omagh bombing 18 months ago, the Provisionals are concerned about the organisation's potential. Its ceasefire was purely tactical.
Despite threats from the Provisionals in the aftermath of the bombing, the "Real IRA" refused to disband. Its leaders continued recruiting, training and buying arms.
Previously its membership was restricted mainly to Border areas. It has now established a foothold in Derry and Belfast and is led by former senior Provisional figures, including the quartermaster-general, who resigned in 1997.
A fortnight ago it issued its first statement since Omagh, calling for support from the grassroots. "The existence of the `Real IRA' poses problems because it means there is somewhere for disgruntled activists to go other than home," says a senior republican source.
Opposition to decommissioning is very strong along the Border, particularly in south Armagh, but the Provisionals have also been experiencing unrest elsewhere, even in normally loyal west Belfast. "Everything can be contained, but only if there is no decommissioning," says a local republican.
The IRA Army Council faced two choices: to decommission to save the peace process or to do nothing and keep its own organisation intact. The desire for unity triumphed.
Sinn Fein and Provisional IRA leaders have managed to sell many compromises to their grassroots: calling a ceasefire without a British withdrawal, accepting the Belfast Agreement, entering Stormont. Why has decommissioning proved so difficult?
Even members who do not support a return to violence are against it. "It is a matter of principle," says a former prisoner. "The guns may never be used again, but I would rather see the whole process fall than hand them over.
"It would criminalise the republican struggle. It would be saying the past 30 years were wrong, that everyone who went to jail, was killed or died on hunger strike was wrong."
Another west Belfast republican says decommissioning would be surrender. "Only defeated armies hand in their weapons. `Decommissioning a few guns wouldn't harm the IRA's military capacity. But it is the symbolism of even handing over a single bullet."
The Ulster Unionists' deadline for decommissioning did not help those within the Provisionals arguing for a gesture. "If the grassroots were ever to agree to decommissioning, it would have to be seen as a voluntary act and not at the behest of David Trimble," says another source.
Even though the Executive will probably be suspended next week, the Sinn Fein/Provisional IRA leadership does not want a return to war, sources insist.
It is also doubtful whether an organisation which has been on ceasefire for almost five years could sustain a lengthy campaign. The 1996-97 campaign was regarded by many republicans as a military failure, nd there is no credible reason for the Provisionals to return to war, having accepted the current political arrangements.
Insiders also insist the leadership does not have the stomach for it. They have become used to a very different lifestyle during the peace process. Sinn Fein knows the huge political gains it has made on both sides of the Border would disappear with a renewed conflict, and it would lose its new friends in Dublin, London and Washington.
Sources say party leaders were concerned about the weight of international media opinion against them on decommissioning this week, but despite the current crisis, the leadership remains committed to the peace process.
Convincing rank-and-file members to make a gesture on decommissioning when the new institutions were functioning was always going to be difficult. Selling a compromise when they have been suspended will be even harder.