Twenty years on from the 1997 IRA ceasefire, what kind of threat does violent Irish republicanism now represent?
The Provisional Irish Republican Army has effectively left the stage. The July 2005 declaration brought its long, armed struggle symbolically to an end.
It is not that there remain no armed remnants of the Provos; history does not proceed as neatly as that. But, as an enduringly attempted insurrection against the Northern Ireland state, the Provisionals are a thing of the past.
However, by 2005, significant breakaway groups had already emerged.
The year 1986 generated a schism which produced the Continuity IRA. And the decisive 1997 ceasefire was followed later in the year by a split from which the Real IRA was to emerge.
More recently, in the past few years, a regrouped dissident republican organisation – simply styled the IRA – has become the most important of the violent republican factions.
This group has nothing like the scale of personnel, resources or support that the Provos enjoyed. Nor do the conditions exist for anything like a return to the levels of violence which scarred the North and beyond during the 1970s and 1980s.
The Provisional IRA represented the most sustainedly significant Irish Republican Army in history to date, and there is no basis for predicting that that standing is about to be eclipsed.
But there are three aspects of violent dissident republican politics which should caution too dismissive an attitude towards these small, aggressive political players.
Actual violence
The first is that their comparatively low levels of actual violence depend not just on the fact that the vast majority of northern nationalists consider such action to be futile. Dissident republican quiescence is also partly due to the ongoing daily activity of the Police Service of Northern Ireland and its UK security colleagues. Dissident violence has varied in capacity over recent years, causing numerous fatalities and many near-misses.
And the reality is that their violence represents a more consistently high level of actual threat in the UK than does jihadist terrorism.
Most people in Britain pay more attention to Isis-related dangers and, in the wake of the Manchester and London attacks, it is understandable that people have a somewhat exaggerated understanding of the risk of jihadist violence.
But the Irish dissident republican threat has, for years, been a more severe one in terms of the violence consistently intended and threatened. And the largely unnoticed actions of the PSNI are a major reason for such threats not making their way, bloodily, into the headlines.
The second point is that, even though they represent a comparatively low level of threat when set against their more substantial Provo predecessors, violent dissidents do have a political effect.
As with previous groups, their impact is very much locally varied. In some localities in the North they have a visible and unavoidable presence. And they do make life more difficult for both Sinn Féin and the PSNI.
For the latter, they make the transition to normal policing, and to unproblematic recruitment from the Catholic community, much more challenging.
For Sinn Féin, dissidents represent a tenacious nuisance, a ghost of past militancy which prevents the party from entirely comfortably securing the ground as the uncontested voice of more hard-edged Irish nationalism.
As Sinn Féin national chairperson Declan Kearney lucidly put it to me in interview, dissident republicans are "an incredibly small minority", but the potential difficulty they pose for Sinn Féin is that that they can "fray the capacity and the coherence of Irish republicanism".
Visible rivals
Because of the violently tinged dissident republican presence, Sinn Féin’s powerful voice has visible rivals within the republican space. Smaller voices, yes, and much less well supported; but a challenge nonetheless.
Dissidents will not deflect Sinn Féin from the route on which they have politically and successfully embarked. But violent dissident republicans continue to represent a brutal rejection of the Good Friday Agreement, and of the political compromises that Sinn Féin republicans have made.
The third thing to acknowledge is the probability that dissident violence is likely to endure long into the future.
I’ve spent most of my life studying Irish nationalism and its complex, fluid relationship with the British state. That long history offers no basis for predicting that there will emerge a fully harmonious relationship between Irish nationalism and a United Kingdom which holds sovereignty over part of Ireland.
This is not to suggest that that sovereignty should end. As things stand, there is not the economic nor the popular basis for such a move.
Nor is it to suggest that dissident republican violence will compel a British disengagement. If the more sustained strength of the Provisional IRA could not violently force the British state to leave Ireland, then there seems no reason at all for thinking that the much punier arsenal of violent dissidents will ever have that effect.
But not succeeding in your central goals as a terrorist group does not mean that you achieve nothing at all. And nor does it necessarily mean that the resistance will end.
The violence of the new IRA will cause appalling suffering for its victims, without generating the kind of historical momentum that its practitioners would like to see.
But even to those of us with little sympathy for their politics, dissident republicanism is entirely explicable.
Yes, there is a criminal dimension to some of the activities involved. And personal rivalries and divisions have also played their part; as so often with terrorist violence, intra-communal dynamics are of high importance.
But the main attraction to dissident republicanism remains political. It involves the uncompromising view that British rule in any part of Ireland is illegitimate, unfair and irreformable, and that this historical wrong can only be put right through violence.
Such a view is politically simplistic, when set against the complex views of the Irish people as a whole. And dissident republican violence will, as I say, cause more agony than political progress.
Enduring conception
But its roots lie in an enduring conception of Irish republican nationalism to which many people over more than a century have adhered.
It has a romantic allure as well as a Pearsean pedigree. It involves a species of nationalist commitment which is recognisable across much of the world. And it is not likely to disappear entirely during the lifetime of anybody reading this article.
Will Brexit make much of a difference? There are so many ironies in the Brexit story that at times it seems to have been scripted by a satirist.
One is that the DUP's parliamentary leverage over Theresa May depended on the Scottish Conservative success of the openly gay Ruth Davidson. (Without the Scottish Tories' 13 seats, the DUP's 10 would not have been decisive.)
But another Brexit irony is surely this. The post-Good Friday Agreement era had seen Irish nationalists become increasingly comfortable with a new era of Irish politics, one in which the porous and flexible Border between North and South had rendered partition less offensive.
But now there is at least the possibility of a more rigid and conspicuous Border after Brexit, and also the prospect that English opinion will pull pro-European Irish nationalists in the North out of the EU.
Neither will cause the Northern Ireland Troubles to reignite. But both will produce some erosion of that nationalist sympathy which existed towards the reformed partition that had been created by the long Northern Ireland peace process.
The DUP is a party primarily committed to maintaining the Union. One crucial foundation stone for the continued Union is its acceptance by Irish nationalists. And, put bluntly, those DUP politicians and voters who have supported Brexit have contributed to the partial erosion of that acceptance.
The July 1997 IRA ceasefire was a crucial step on the journey towards peace in Ireland, and we should not forget what a huge change has been effected.
The high levels of violence which cruelly hurt people on all sides in the Northern Ireland conflict have been decisively and lastingly reduced. But dissident republican violence will continue into the future, albeit at comparatively low levels.
That it does so is historically explicable, however unjustifiable and overwhelmingly futile it remains. And the politics of polarisation that have been so evident in recent months in the North do little to make the threat any lighter.
Richard English is professor of politics at Queen’s University Belfast. His books include Armed Struggle: The History of the IRA and Irish Freedom: The History of Nationalism in Ireland.