Thursday night’s stinging claims by Martin McGuinness and Peter Robinson’s thunderous response has shattered what has long appeared to have been a non-aggression pact between the two men.
While both have used party underlings to attack the other, direct public confrontation between Stormont Castle’s joint rulers has until now been adjudged to be counterproductive.
Such has been the imperative to preserve relations between both men, that in Peter Robinson’s fiercely-worded attack on Sinn Fein there wasn’t a single word of direct condemnation aimed at his Stormont Castle opposite number.
Martin McGuinness’s comments on The View appeared to have been carefully weighed and possibly designed to provoke the response which within hours had arrived from his DUP opposite number.
Mr Robinson’s venomous response — which used the word “dictator” to describe his OFMDFM partner — was released by his party at 1.26am: clearly Mr Robinson was as “fed up” as Mr McGuinness professed himself to be.
There is no doubt that relations between Stormont Castle’s leaders have been increasingly strained over the last six months.
But, whether intentional or otherwise, the ‘crisis’ at the top of the Executive has — at least for a day — taken the focus off Ian Paisley’s impending and brutal assessment of the party he founded and the man who succeeded him as leader.
It has also reminded people of how close Dr Paisley and Mr McGuinness were, laughing and speaking warmly of one another, at a time when Dr Paisley’s removal as leader is going to be re-examined.
That, however, can hardly have been the main consideration for either man, given how such public rows undermine their attempts to portray the Executive as coherent and functional.
And, while it is easy to make statements attacking one another, de-escalating the rhetoric can be much trickier.
By lunchtime yesterday, when Mr Robinson addressed the TV cameras, he sounded as though he had rowed back somewhat from the overnight thunderbolt, describing Mr McGuinness’s comments as “unhelpful” to “take the pin out of the grenade”.
Heading towards elections in May, there are likely to be increasing spats between the DUP and Sinn Fein.
But however tetchy such exchanges may get as each party seeks to energise its base to get out and vote to stop the other topping the European election poll, each faces a fundamental reality: Short of collapsing the Executive, each needs to work with the other — even though neither likes the fact.