By Mike Wooldridge
BBC News, Baghdad
It is not decommissioning of arms that is the crucial issue but decommissioning of mindsets, Andrew Sens like to say, quoting what he calls a wise man involved in the Northern Ireland peace process.
The scale of violence is vastly different but there are similarities
Mr Sens, an American career diplomat who serves on the independent international weapons decommissioning body in Northern Ireland, has been in Baghdad with Finnish colleague Brigadier-General Tauno Nieminen to offer their experience of a decade of overseeing the effort to remove paramilitary weapons from circulation.
Getting weapons out of the hands of the many insurgent and militia groups in Iraq may seem a decidedly distant prospect - and the two men are not predicting that any such thing could happen in a short period.
But they are looking ahead to a time when even this violent and increasingly fractured country could find its warring factions tiring of conflict.
"The scale of violence is, of course, totally different from Northern Ireland," says Brig Gen Nieminen, "but there are similarities."
Most obviously, the bombings - which have returned to Baghdad with relentless vengeance in recent days.
And then the insecurity people experience, in their daily lives in the capital and in contemplating the future.
Moqtada Sadr is a powerfully divisive figure in Iraq
But another similarity is one that undoubtedly complicates the task of decommissioning weapons, if and when the situation stabilises sufficiently in Iraq for such a process to get under way.
It is that people will often see groups that commit violence elsewhere as protectors of their own embattled communities.
An example of that in Iraq would be the Mehdi army, the militia associated with the radical Shia cleric, Moqtada Sadr - the powerful group that is expected to be a particular focus of the new Iraqi-US security operation.
If they have brought a message to Baghdad - and they are careful not to call it advice for the Iraqi government - it is that reducing the number of weapons in circulation requires a great deal of patience, accepting that you cannot eradicate another person's ideas, being prepared to engage in dialogue and to listen carefully.
They say their experience of the Northern Ireland decommissioning process has shown that the political process is crucial - when the political parties become bigger players in resolving differences then the paramilitary role becomes less important.
"Peace comes in very small steps," Brig Gen Nieminen says. "You cannot achieve everything at once. You have to begin slowly."
He has other experiences that might seem relevant.
He was head of a border monitoring mission under the auspices of the International Conference on the Former Yugoslavia and has seen the impact of the break-up of a country.
Some predict the same, eventually, for Iraq.
But he says that in former Yugoslavia people wanted to be separated and in their discussions with Iraqis he did not find that to be the case. "Whether Sunni or Shia," he says, "they talk of themselves as Iraqis."
If there is ever to be a formal weapons decommissioning process in Iraq, would it be overseen by third parties?
Might Iraq's neighbours be involved - Iran, perhaps, on the grounds that it might secure the trust of Shia armed groups? Such issues are clearly some way - perhaps a long way - down the road.
History will show whether the Northern Ireland example has any influence here.