Palace Barracks breach boosts dissident republicans after a series of setbacks
What a difference a few days make in the lives of dissident republicans opposed to peace and power-sharing.
Earlier this week they were the subject of some ridicule from their rivals and enemies over the destruction of a litter bin by one of their bombs in Derry.
This followed on from the discovery of a mortar bomb device in a Strabane graveyard, and later in the same spot the recovery of a rifle.
Add to the above the scores of arrests and terror operations nipped in the bud by An Garda Siochana and the PSNI, including a possible bomb to mark Prince Charles' historic visit to the west of Ireland, and you could reasonably conclude that the anti-ceasefire republican armed struggle was heading for ignominious defeat.
However, yesterday's bomb inside a Royal Mail van within the security perimeter of Palace Barracks in Holywood marks something of a small but significant morale boost for the hard-line republicans. Mercifully, no one was injured in the blast, but the mere fact that one of the republican factions managed to slip through the 24/7 surveillance/intelligence net around them and then get a bomb past security at the gate is a clear signal that they remain a serious threat. This Trojan Horse-style operation demonstrated not only ruthlessness, but guile and planning in the way it was executed.
MI5's regional HQ is meant to be one of the most secure complexes anywhere in the UK, leaving aside the fact that there are also hundreds upon hundreds of Scottish soldiers and their families living in the same base.
Palace Barracks remains high up on the dissident republican target list as it is seen by them as a physical representation of continued British rule in Ireland. Remember back in 2010 when they forced a terrified taxi driver to take a bomb right up to the base's back gates. That attack was not just about the place, but also the time.
The bomb went off just hours before policing and justice powers were handed over to the Northern Ireland Executive. The explosion was a reminder from recalcitrant republicanism that the real powers of security still lay inside the complex that they were attacking because MI5 took over the prime role of counter-terrorism in Northern Ireland and Britain. As the old Provo saying goes, they only have to be lucky once!
They almost did yesterday morning, but luck was on the side of those who had parked their cars or were passing by when the device detonated. Crucially, too, this act of armed propaganda also sends out a message about chatter and conversations going on all through the summer about a possible ceasefire or suspension of armed activity by some but not all of the dissident groups.
Even if, as seems highly plausible, the internal debate is still going on about the efficacy of "armed struggle", there are still enough diehards out there to give the security forces a headache - and in this case cause some serious embarrassment.