I make no apology for returning again to the breakdown in the peace process. I believe that, despite the amount which has been written on this subject, insufficient attention has been given to the circumstances that led to this breakdown - circumstances that I believe may help to explain why there has been so much post-breakdown bitterness between the two governments and Sinn Féin/IRA.
Up to last December, the Irish Government had been content effectively to ignore major robberies by the IRA, so long as these were confined to Northern Ireland - and the British government had seemed to tolerate major robberies in its jurisdiction. The two governments may have assumed, or hoped, that the IRA would understand that this tolerance was a temporary tactical move, designed to keep IRA activists happy until the end of the process.
However, the IRA seems to have interpreted this tolerance differently. For, when the crunch came, the statement made on its behalf on this criminality issue pointedly deleted from the text of what had been sought by the two governments the words that would have made it unambiguously clear that all criminal activity - as these words are understood in law, and not as subjectively defined by the IRA - would cease.
It would appear that, as a result of this earlier tolerance of IRA criminal activity, that organisation had come to believe that the two governments would accept, for the purposes of a settlement, the residual wording, designed to permit them to continue deciding for themselves what was or was not criminal activity.
For the IRA, that expectation may have seemed to have been validated by the fact that, in the immediate aftermath of its rejection of the two governments' proposed wording, those governments persisted in claiming that the only remaining significant obstacle to a final agreement was the DUP's provocative demand for photographic evidence of decommissioning.
The rejection of the anti-criminality wording by the IRA seemed to evoke no adverse reaction from the Taoiseach or Minister for Foreign Affairs or from the British government. Thus, when the Tánaiste instantly went public with a suggestion that there remained another outstanding problem in addition to that of photographic evidence of decommissioning, and the Minister for Justice then publicly identified this problem as the refusal by IRA/Sinn Féin to commit themselves unambiguously on the criminality issue, the Taoiseach and the British prime minister were overnight forced by this PD stance to reverse engines: the whole fragile house of cards then collapsed.
As a result, instead of the breakdown in negotiations being attributed to Ian Paisley's demand for photographic evidence of decommissioning (designed, in Paisley's words, to "humiliate" the IRA), the blame for the breakdown instantly shifted to the IRA's refusal to commit itself to dropping criminality.
This sudden and unexpected reversal of fortune clearly infuriated Sinn Féin and the IRA, and that may have contributed to a decision to rob the Northern Bank. Unfortunately, the subsequent switch in public attention to that robbery (responsibility for which is, of course, still disputed by IRA/Sinn Féin) had the effect of diverting public attention away from the crucial refusal of the IRA to agree to abandon criminality.
It was notable, and I felt disturbing, that in last Monday's Questions and Answers programme, which was devoted to this matter, the attention of all the panellists and of the audience was focused exclusively on the controversial robbery - in respect of which the IRA and Sinn Féin denials provide their more credulous supporters or sympathisers with some kind of cover. Astonishingly, no mention was made by any participant of the significant public refusal by the IRA to commit itself to abandoning criminality.
It is clear that Sinn Féin/IRA is facing severe internal tensions, and these can best be alleviated by concentrating attention on, and disclaiming responsibility for, the bank robbery - thus distracting attention from the criminality issue.
The governments, for their part, seem also to have been content to highlight the Belfast bank robbery, perhaps in the hope of distracting attention from their earlier mishandling of the crucially important criminality issue, although by doing this they seem to me to have played into the hands of Sinn Féin and the IRA.
I am totally unconvinced by those who seek to dismiss the criminality issue on the basis of what seems to me to be an extraordinarily naive belief that if the IRA was allowed to get away with refusing to abjure criminality unambiguously while at the same time its political party, Sinn Féin, was allowed to achieve its current key objective of becoming involved in policing, all would be well.
But what kind of credibility would a policing system have if one of the parties responsible for its administration was allowed to insist on the right to decide that crimes committed by its IRA associates were not to be treated as crimes? Criminality, as the law defines it, must be abjured unambiguously by the IRA before it and its Sinn Féin associates are allowed to take their places in its management and staffing. If we abandoned that fundamental principle, we would be threatened with anarchy. As someone who has backed the peace process from the outset, I am glad that, after these recent events, this criminality issue can no longer be fudged.
Behind all this there lies a more fundamental problem which no one seems to want to address: the growing alienation from each other of nationalists on either side of the Border. Of course, there have always been tensions between nationalists North and South. Northern nationalists greatly resented what they saw - with reason - as their effective abandonment by their Southern compatriots between 1925 and 1969.
And, as memories of past grievances and sectarian tensions in our evolving southern society have gradually faded, and relations between Catholics and Protestants in the Republic have normalised, for nationalists here the bitterness between the two communities in the North has come to seem increasingly anomalous.
Nevertheless, so long as, throughout the years of violence, the SDLP remained the principal voice of Northern nationalism, the relationship between nationalists North and South was kept on an even keel.
However, now that a majority of Northern nationalists have transferred their allegiance to Sinn Féin, with evident tolerance of the IRA, this relationship between northern and southern nationalists has become more problematic.
When people in this State are told by our media about alleged widespread tacit approval of the Northern Bank raid among northern nationalists, they begin to feel closer to unionists in the North. And when northern nationalists observe this kind of shift in opinion in the South, they start to feel alienated from us. These are not healthy developments.