In purely political terms, the highest praise possible for Mike Nesbitt’s dramatic exit from the Executive is that it is almost certainly what Peter Robinson would have done if he had been in this position.
In fact, Mr Robinson – a masterful exponent of opposition politics – did something remarkably similar to what happened on Wednesday when he and Nigel Dodds quit the Executive in 2002 after the exposure of an IRA spy operation at Stormont.
Although Mr Robinson will not appreciate the comparison, the similarities with the two situations do not stop there. At that point, a weakened David Trimble’s response was to seek a meeting with the Prime Minister, although he conceded that the gravity of the situation was likely to collapse the Executive.
The two scenarios are not entirely analogous, but the DUP is giving every indication that it wants to stay at the Executive table, despite the growing cross-party belief that the days of this present Stormont are numbered.
The DUP response to the UUP – which came four hours after the news broke, and from Mr Dodds rather than from Mr Robinson – gave no suggestion that the party was preparing to follow the UUP out of the Executive and included a request for an “urgent meeting with the Prime Minister”.
A significant section of DUP members – and more significantly, its voters – do not want to see the party remaining in government with a party linked to an IRA which still has guns and which uses them to carry out murder.
But rather than walking away from the Executive, the DUP leadership is instead arguing for as yet unspecified sanctions against Sinn Fein, saying that it is republicans – not unionists – who ought to be punished for the alleged actions of IRA members.
An exclusion motion in the Assembly would simply be vetoed by Sinn Fein, and after that the DUP would seek to pressure the Government.
In a move which could well define Mike Nesbitt’s leadership, the UUP is now likely to formally quit the Executive on Tuesday and has seven days to nominate a replacement minister, after which the Assembly would have to be convened and the DUP – who are next in line for the seat – would be asked to nominate a minister.
That gives Mr Robinson limited time, and makes his favoured tactic of stalling for time – such as over the on-the-runs issue – more difficult.
Mr Nesbitt has provided maximum political discomfort for his DUP rival and if Mr Robinson comes under sufficient pressure to quit the Executive then that will be the end of this Stormont.
If that was to happen, history suggests that there will be several wilderness years of direct rule.
After the 2002 suspension of Stormont it took five years for devolved government to return – under new leaders of unionism and nationalism.