IN common with RHI – a scandal that in any other jurisdication would've probably cost Arlene Foster her job – the controversy around the Executive Committee (Functions) Bill came from left field and doesn't automatically conform to the usual divisiveness that characterises so much of the north's politics. This is arguably more about competency than any ideology.
Her own MPs and assembly members are now left wondering if the Fermanagh and South Tyrone MLA is "across every jot and tittle", as her role demands.
Her former special adviser Richard Bullick very publicly highlighted what he saw as problems with the legislation and how he believed it relinquished safeguards on 'solo runs' secured by the DUP at the 2006 St Andrews Agreement.
Latterly, senior DUP MPs urged the first minister to apply the brake to the bill's accelerated passage yet it appears Mrs Foster's stubbornness prevented any climbdown.
Her backroom staff are also said to have been steadfast in their determination not to concede an error of judgement. "Cack-handed" and "appalingly handled" is how one of the party's Westminster representatives last night described the events of recent days.
But while the scale of Tuesday's rebellion and accompanying bewilderment is unheard of, it looks like Mrs Foster will ride out this particular storm on the basis that there is no obvious candidate to succeed her.
Sir Jeffrey Donaldson lacks the necessary ruthlessness to mount a heave against his former UUP colleague, while Nigel Dodds banishment from the green benches has all but rendered him impotent.
Ian Paisley is too much of a maverick and among the DUP's assembly team, there are slim pickings in terms of a potential successor.
She may remain DUP leader in name but there is no doubt that Mrs Foster's credibility has been badly damaged. It is one thing to be criticised by opponents but to be publicly humiliated by those who are supposed to be your most loyal supporters can only undermine her confidence and fuel paranoia.
Winning back the support of the backbenchers, many of whom are sceptical about power-sharing, will be a difficult task for the DUP leader and one that certainly won't be achieved by making any concessions to nationalism.
