Most important part of her 2011 trip was one divorced from the public

A huge security ‘cordon-sanitaire’ had been erected around north central Dublin on that historic morning when the Monarch visited the Garden of Remembrance.

The various, disparate factions of Irish Republicanism gathered to protest against her presence were huddled around nearby Charles Stewart Parnell’s statue – the monument to a man who ironically only advocated peaceful, constitutional change rather than the violent insurrectionism of the Fenian movement.

What was striking about the hours before the Queen’s heavily guarded cavalcade arrived in the memorial garden to the Irish Republican dead of 1916 to 1921 was that those demonstrating were not only heavily outnumbered by the Garda Siochana and Irish soldiers but also appeared impotent and irrelevant.

Among the diehards behind the Parnell plinth was the late Ruraidh O’Bradaigh, the IRA veteran and founder of Republican Sinn Fein.

I went over to him and asked what he thought of this once unthinkable occasion.

He looked up the street towards a knot of younger men who in turn seemed more focused on Mr O’Bradaigh and his colleagues than on the entrance to the garden.

“They’ll be joining the royal celebrations soon enough,” O’Bradaigh cackled cynically, meaning the group of Sinn Fein activists watching on across the road from the famous Gate Theatre.

After I made my excuses and left for the ceremony, I was accosted by one of the Sinn Fein members, an officious young man with cropped red hair who had something he wanted to say. He explained that while Sinn Fein were there to observe they were not part of the demonstrators down at Parnell’s statue, and that I should not confuse this in my reporting. I got the distinct impression that this chap and his comrades were there as much to keep an eye on rival republicans than they were to witness what was going on inside the Garden of Remembrance.

Beyond the Queen laying the wreath in memory of the Republican dead there were other memorable moments.

I loved the sight of the Duke of Edinburgh holding a hurling stick inside Croke Park as well as him salivating over a pint of the black stuff inside the Guinness factory.

But the prophecy of an old, hardline republican kept rattling around my brain throughout the entire visit and was amplified a year later when Martin McGuinnness shook hands with the Queen in Belfast’s Lyric Theatre.