It's an Assembly that is not fit for purpose - McGuinness quitting is just the final straw
RHI scandal delivered coup de grace to system unable to deal with any crisis in a grown-up way
The demand that Arlene Foster steps aside pending an investigation into the Renewable Heat Incentive (RHI) is entirely reasonable and appropriate and is supported not only by the Opposition, but a wide range of public opinion.
Foster's refusal to step aside temporarily on a 'without prejudice' basis to allow an investigation to take place, despite the fact that her predecessor Peter Robinson did the same, is indicative of her lack of flexibility and her arrogance as a leader. This may, ultimately, be fatal to her continued leadership of the DUP.
Sinn Fein, for fear of being outflanked by the SDLP and the UUP as they were before Christmas, believes that it must be seen to be as tough as the Opposition in relation to Foster's position as First Minister.
It knows that grassroots nationalist and republican opinion supports the SDLP and UUP's joint position - that Foster has to step aside pending a public inquiry into the whole RHI affair.
However, while originally supporting a full public inquiry, it has rowed back from that position and is saying that a public inquiry is not necessary, but that a smaller-scale independent investigation would be sufficient.
Republican grassroots opinion has been aggrieved at the hitherto softly, softly approach by Sinn Fein to the RHI scandal and Foster's involvement in the policy-creation aspect of the scheme.
Having been uncertain and contradictory in relation to this unexpected crisis, it is now trying to re-establish its credibility with its own supporters.
Therefore, the decision by Martin McGuinness to resign as Deputy First Minister is clearly a response to the growing discontent among Sinn Fein members and supporters with the way the crisis was being handled by the party prior to Christmas.
Foster's refusal to step aside meant that McGuinness had little option but to press the nuclear button and resign, bringing down the current Executive and at the same time raising the prospect of an early Assembly election.
Ironically in all of this, it is probably McGuinness who is the most reluctant of all in Sinn Fein to support this development.
As Deputy First Minister he must surely have wished to retire, not resign, from the office with a successful political legacy, not one of collapse and ultimate political failure.
If elections do take place - and there is still a narrow time-frame in which to avoid this drastic step - the likeliest result would be a largely unchanged Assembly, with the same type of political make-up and balance as the present one.
Worse still for Sinn Fein is that Foster would probably be returned with a fresh electoral mandate for her to continue on as before, and not to stand down pending any inquiry.
If that was the result, then we would be back to square one.
In addition, for Sinn Fein an election will mean some pain as it is likely it will lose about five seats given the numerical reduction of MLAs down from 108 to 90.
The use of the nuclear option by Sinn Fein will be politically popular with its disgruntled supporters and will undoubtedly do much in restoring Sinn Fein's street credibility throughout the north.
The problem is that this move will be futile in achieving the purported goal of Foster stepping aside and breaking the present impasse.
This debacle has further eroded people's confidence in politics here.
Previously, legacy issues, continued paramilitary activity and the strains on the health service have all conspired to make politics here more and more discredited.
The RHI scandal is simply the coup de grace.
But why is it that?
With every crisis we have here, there is a real threat to the very existence of the Assembly itself.
This does not happen in any other political system.
The Westminster parliament can survive the change of a PM, or indeed sometimes even a Government, without threatening the very existence of parliament itself.
Are we so incapable and so immature that we are simply unable to deal in a grown-up way with political crises without the threat of collapse being played by one side or other?
Surely we can negotiate our way through to political agreement that leads to prolonged political stability?
What is certain is that our politics will remain discredited, destabilised and in an sterile state if we do not end the seemingly endless and wearisome political crises that undermine the very existence of the Assembly itself.
The system has to move from mere crisis management and containment to a crisis-proofed way of constructively managing our politics.
Maybe now is the opportunity to do just that with a radical reconstruction of the current Assembly system that can successfully address this inherent problem.