Direct Rule of Northern Ireland by the British government ended at midnight on December 2nd, 1999, when power over policy relating to the North reverted for the first time in 25 years to a democratically-elected devolved government at Stormont.
However, should the current impasse over decommissioning remain unresolved, the North's experience of self-rule may be short-lived.
When the Belfast Agreement finally came into force early last December it led to a series of constitutional and institutional changes for the Republic, Britain and Northern Ireland. The most tangible evidence of a suspension of the institutions established under the agreement would be a halt to the work of the 108-member Assembly at Stormont and the Executive.
This scenario would require the introduction of new legislation at Westminster.
During a suspension period the British and Irish governments, along with the Northern parties, would undertake a review of the Belfast Agreement. Their mission would be to save the agreement by securing a start to the decommissioning of paramilitary arms.
The British government has already prepared draft legislation to provide for a suspension of the Assembly and the other institutions established under the Belfast Agreement. This draft legislation was presented to the North's political parties in July 1999 as part of the failed discussions at Castle Buildings to end the impasse over decommissioning and formation of the Executive.
The draft Northern Ireland Bill provides a model for the suspension of devolved government in the North. During a suspension period neither the Assembly nor any of its committees would be able to hold any meetings or conduct any business.
However, the draft legislation requires the Secretary of State to call two meetings of the Northern Assembly. The first would be held within seven days of the making of the suspension order at Westminster. The Assembly would debate, but not vote on, the situation which led to suspension of the institutions.
The second would be held within seven days of the conclusion of the review of the Belfast Agreement.
It was not clear last night whether this legislative model from July 1999 would be reactivated. Nevertheless, the consequences of such legislation would be to return to the Secretary of State responsibility over the policy areas which, since early December, have been controlled by Mr David Trimble and his colleagues on the Northern Executive.
In effect, Mr Mandelson and his junior ministerial colleagues would discharge the functions of the First Minister and the other Ministers.
At the end of a suspension period, should progress be achieved on decommissioning, the Ministers and other officeholders would resume their positions.
Two other institutional aspects of the Belfast Agreement would also be affected by a suspension: the North-South Ministerial Council and the British-Irish Council.
The Belfast Agreement notes that the North-South Ministerial Council will "bring together those with executive responsibilities in Northern Ireland and the Irish Government". It is thought likely that control from the British side over the cross-Border Implementation Bodies would be transferred to the relevant government departments in the North.
In recent weeks ministers from Dublin and Stormont have been meeting to further cross-Border policy co-ordination. Only last week the Tanaiste, Ms Harney, met her Northern counterpart, Sir Reg Empey. However, with any suspension of the institutions, that work may be difficult to advance in the absence of any serious political input from the North.
Regardless of what happens at institutional level, the Irish Government will continue to have an important role in the direction of policy over Northern Ireland.
The two governments will continue to discuss issues of mutual concern relating to the North through the British-Irish Inter-Governmental Conference. During a suspension the conference would be able to discuss any item which would previously have been within the remit of the Assembly and Executive.
The ongoing manoeuvrings have no impact on the constitutional changes approved by the Irish electorate when it endorsed the Belfast Agreement in May 1998. When the revised versions of Articles 2 and 3 came into effect last December, the Taoiseach told the Dail that the wording encapsulated our modern understanding of constitutional republicanism. He commented: "The last traces of irredentism are gone."
Mr Ahern asserted that the new Articles were now "irrevocable". However, he did foresee the possibility of trouble down the road when he admitted that he could not envisage a situation, even where the functions of the Belfast Agreement had been interrupted for a considerable time, in which "the parties in this House or the people would wish to revert to the previous wording".