The murder of Andy Kearney in Belfast this week has cast a long shadow over the peace process. In the early hours of Sunday morning 33-year-old Mr Kearney was taken from his flat in the New Lodge area of Belfast, where he was living with his girlfriend and their two-week-old daughter.
Five men burst into the flat and ordered the young mother to take the baby into another room. They then dragged Mr Kearney to a nearby lift and shot him three times in the legs.
Before they left, the attackers ripped out the phone, so that his girlfriend was forced to run to a neighbour's flat to call an ambulance. By the time she got one it was already too late. An artery in Andy Kearney's leg had been severed and he bled to death on the way to hospital.
The RUC has described his death as a "cold-blooded murder with all the hallmarks of a paramilitary shooting".
As so often in Northern Ireland when atrocities of this kind happen, there have been suggestions that the attack may have been connected with drugs. Even if that had been the case the manner of the killing would have been barbaric. But the police are emphatic that Mr Kearney had no connections either with drugs or with paramilitary activity.
His family believes that the shooting was connected with a republican vendetta, that Mr Kearney, who was described as "a bit of a hothead", had been part of a fight which also involved a prominent republican from west Belfast.
His mother, 65-year-old Maureen Kearney, had already made efforts to intercede on his behalf with the Sinn Fein leadership in the area. After his death she said: "If they don't like you they dispense with you."
Sinn Fein is clearly highly embarrassed by the murder. Gerry Kelly, who is an Assembly representative for the area, described it as "an appalling incident which should never have happened" and said his party was doing all it could to stop such attacks.
But in the wake of Drumcree and the murder of the three small Quinn brothers, such public hand-wringing is no longer enough. Philip McGarry of the Alliance Party compared Mr Kelly's comments to the efforts of David Jones and Ian Paisley to claim that the Ballymoney killings were a random act which had nothing to do with Drumcree.
The nightly confrontations between loyalists and the RUC at Drumcree, the catalogue of attacks on Catholic homes, these have distracted attention from other acts of brutality which have equally serious implications for political progress in Northern Ireland.
In the wake of Mr Kearney's murder Jim Cusack, this newspaper's Security Correspondent, detailed a horrifying increase in so-called punishment attacks.
RUC statistics show that there have been 122 such incidents this year. Republican groups, mainly the Provisional IRA, have been responsible for 31 shootings and loyalists for 19.
This compares with figures for the first six months of l977, when republicans carried out four punishment shootings and loyalists 32. However, to keep the balance accurate, loyalists are thought to have carried out 44 of the 72 punishment beatings, republicans 28.
These attacks have received relatively little media attention, despite the efforts of groups like Families Against Intimidation and Terror. Journalists like myself (mea culpa) have tended to regard them as a deeply regrettable hangover from 30 years of violence, part of the long and painful progress towards normality in Northern Ireland.
We condemn them, but we still see them as part of the problems associated with policing which will only be cured, like so much else, with the implementation of the Belfast Agreement.
The first consideration must be one of common humanity, of revulsion for the grief and terror such episodes cause throughout the whole community. But the fact that such attacks have increased over the past year has extremely serious political implications for the period ahead.
The Mitchell Principles, setting out the conditions for participation in talks and the political process, specifically condemn punishment attacks and urge parties with links to paramilitary groups "to take effective steps to stop such activities". Earlier this year there was a major crisis in the talks process when the two governments decided that Sinn Fein should be banished for a week following the killing of a drug dealer in Belfast.
This week, as the Bill setting up the new Assembly and the political structures associated with it had its second reading in the House of Commons, the issue came up again.
David Trimble told MPs that if he were faced with an incident like that of Mr Kearney's murder, he would have no option but to move that Sinn Fein should be excluded from taking seats on the new executive.
What would the two governments do if this were to happen? How would Seamus Mallon react? The Deputy First Minister tried to smooth over the problem in parliament this week, but would find this much less easy if the Assembly was actually sitting. He is known and respected for his passionate commitment to the principles of non-violence, and his outspoken condemnation of the IRA is one of the main reasons that unionists trust him.
Other SDLP figures have been blunt about the political repercussions. Martin Morgan said the murder of Andy Kearney and other such attacks played right into the hands of those unionists who want to wreck the agreement. They will certainly increase the pressures on David Trimble to be tough on related issues like the decommissioning of paramilitary weapons.
Drumcree and the deaths of three small, irreplaceable children have forced a radical rethink within the Orange Order and right across the broader unionist community.
The courage of the Rev William Bingham in articulating that deep unease about the connection between the Orangemen's standoff and the deaths of the Quinn brothers, the resignation of other chaplains, the questions that have been asked publicly about where the Order is going, all these are important signals of hope from those bitter July days.
They do not comfort those who are left to grieve, but they make some sense of what happened for the rest of us.
We can only hope and pray that the death of Andy Kearney, although it has not caused the same public outcry, will encourage a similar process of re-examination and conscientious debate within the republican movement and the broader community which it represents.
If that happens, his death and the grief of his family will not have been entirely in vain.