It has been a bruising week for Sinn Féin. New disclosures about the party's mishandling of child abuse by republicans and the dispensing of summary justice has propelled them from the celebratory hubris of last weekend's Ard Fheis to a major political storm north and south.
In the North, Martin McGuinness's shock announcement of rejection of the welfare reforms, agreed in all-party talks last Christmas, has destabilised the power-sharing executive and poisoned relations with Peter Robinson.
Both sides claim bad faith and disagreement about the scope of the deal.
The compromise extracted at the time, which was to financially compensate everyone affected by the cuts, always looked like a cosmetic exercise - a face-saving ploy for Sinn Féin, while at the same time allowing them to pander to their ever populist anti-austerity agenda north and south.
This surprise change of mind and position emerged out of the Ard Fheis in Derry last weekend and is in response to an unprecedented mobilisation of trade unions against the reforms, which include the loss of 20,000 public sector jobs.
The party is in election mode. Riding high on favourable opinion polls, deputy leader Mary Lou McDonald asserted with confidence that the party is ready and "fit" for Government.
But many observers this weekend would question the claim of "fitness to govern".
The truth is, while voters in the Republic welcome the strides made by Sinn Féin away from their IRA twin's subversion and terrorism to democratic politics, most remain queasy at the prospect of them in Government in the Republic.
There are just too many unanswered questions, unsolved murders, missing bodies, unsavoury associations and activities which can be linked to the party for a line to be drawn to the point of fitness to govern in the Republic.
Mairia Cahill, a brave woman by any measure, given who she is taking on, exposed the murky past of republicans when dealing with her rape and this week more such cases have emerged in the Irish Independent and BBC 'Spotlight' investigation, which highlighted the rape and subsequent death threats against Paudie McGahon when he was 17.
The families of the 'disappeared', whose protracted pain was explored in a documentary last week, reminds us of how the past is not yet dispatched to history. There are many wounded people, victims of republican violence and intimidation who remain unsettled by the unstoppable political march of Sinn Féin away from the detritus they left behind.
Sinn Fein are by far the wealthiest party in the Dáil thanks to their American donors and State funding on the basis of their Oireachtas representation.
For a party wedded so long to subversion and violence, they have taken to politics like ducks to water.
On one level, we should welcome this as a sign that politics is working for them and they can pursue their political aspirations exclusively through democratic means. What they actually stand for in the political space, apart from anti- austerity populism, is not so clear.
They style themselves as a radical left-wing party of working people; aligned closely with Syriza in Greece and Podemus in Spain. The attendance of a Greek minister at the Ard Fheis was a pointed sign of association with the new anti-austerity government in Greece.
The trouble with all this talk of SF being in government is that it overlooks the inherent conservatism of the Irish electorate when it comes to choosing a government. In my opinion, with signs of recovery emerging, however late in the day for this Government, the Irish electorate will be loath to risk instability and radical change with unknown outcomes.
Sinn Féin's reneging from the agreement reached on welfare reform in the North also reflects poorly on their claim of being fit to govern.
Irish officials will recall during the peace process the Sinn Féin propensity to press hard for concessions and immediately pocket them when achieved. There was never a sense of an ending to their demands.
What the party has yet to learn is that negotiated political deals normally fall short of optimum. For a compromise deal to be genuine, there has to be parity of pain and parity of gain for everyone. Sinn Féin have no appetite for the pain and fallibility of politics. On the contrary, following recent election gains, there are signs of self- deluded hubris in their approach.
They take umbrage at being challenged by the media and in the Dáil.
Their call for an all-island sex abuse initiative is a masterpiece of distraction away from accounting for their own failures in reporting sex abusers to the authorities.
Rejecting the deal on welfare reform is reckless.
Causing instability and discord with their unionist colleagues in government apparently counts for nothing when set against the lure of populist vote- getting north and south.
Robinson and McGuinness can fake unity abroad but closer to home they are political foes.
And still the dollars from misty-eyed Irish Americans flow in to support the "peace process".
The irony is that the radical politics espoused by Sinn Féin - and the recent disclosures of sex abuse cover-up - would be abhorrent to those very same donors.
Paudie McGahon, whose claims include rape and being subjected to a terrifying internal inquiry by the IRA as recently as 2002, chillingly described Sinn Féin as "somewhere between a cult and the mafia".
It may be that the Teflon-like Mr Gerry Adams can survive these latest damaging developments as so often before, but the bona fides and fitness to govern of his party has been steadily eroded in the minds of most fair-minded observers.
This suggests that the Eldorado of Sinn Féin being in government north and south of the border may be out of reach for some time to come.