The Irish peace process has delivered huge advances and saved many lives but it has yet to deliver political stability, as the latest crisis in Belfast demonstrates with such dismal clarity.
The political process does not depend on love between ancient enemies in the administration which is headed by the Democratic Unionists and Sinn Fein. But it does require a modicum of give and take to keep it functioning. This has been absent.
This is partly because the DUP's Peter Robinson has opted to play a particularly long game since he took over as First Minister in June 2008. He has held up the devolution of policing powers to Belfast despite the fact that practically all other elements want to make the move.
The sense is that he has been motivated not by triumphalism but by nervousness about the growling dinosaurs who populate parts of the Protestant grassroots, including sections of his own party. An additional reason for his inaction, now obvious but unknown over those frustrating months, may have been the sensational saga of his wife, Iris. For more than a year he tried desperately to keep everything strictly secret, adding an extra layer of Ulster Presbyterian repression to his political strategy.
But now the Iris secret is out, as is the curiously parallel affair of whether Sinn Fein president Gerry Adams reacted strongly enough after discovering, more than two decades ago, that his niece had allegedly been abused by his brother. Above all else, the DUP are anxious to avoid Assembly elections since they fear, almost certainly correctly, that with the Iris Robinson affair so fresh in the minds of voters they could lose many seats. They could lose their key status as the biggest Northern Ireland party; in fact, their successors could be Sinn Fein.
The threat of an election was probably the strongest card in the hands of prime ministers Gordon Brown and Brian Cowen as they flew into Belfast yesterday. Since it is abundantly clear that he will not act voluntarily, they will be intent on telling Mr Robinson politely but firmly that the two governments are taking charge, that he can have no more veto on movement, and that the time for inertia is over.