Peter, what I'm going to postulate here is PURE SPECULATION, but it is based on some knowledge of the Irish-English antagonism that dates from the 1600s and only in the last twenty years has begun to wane, ever since the Good Friday accords of 1998 (the day was quite symbolic).
If we bear in mind that the Irish have a long memory of English antagonism (I personally understand this being of Irish-English heritage); and the Irish considered themselves enslaved by the British (every "real Irishman" can cite the Battle of the Boyne -1690, or the Potato Famine -1849-52, or the Bloody Sunday Massacre -1920 as defining moments in their history), then what I'm speculating has some relevance. Ireland saw itself as a divided country, with 1/6th of its land mass still partitioned off as Northern Ireland, a part of Great Britain. In Irish eyes, Northern Ireland sat as the site of an alien occupational force.
In 1949 Ireland was finally declared a Republic, receiving full autonomy of rule from England. Sinn Fein and the IRA were still very active (many of us still recall the IRA bombings in London only a few decades ago).
It is fully possible (although I have never seen documentation on this, and if there is any, it would be in the heads of the IRA) that Ireland was thinking about arming a citizen militia (much like colonial America did) to reclaim Northern Ireland with a citizen's force (lead by the IRA) marching on Belfast -- a liberation from the evil oppressor and a unification of the country.
Now this might seem far-fetched in today's world, but, as an amateur historian, I can say it would not be outside the realm of possibility in 1953-4. Obviously it didn't happen, and saner minds prevailed. But given the history of Sinn Fein and the IRA between 1949 and 1998, a "free Northern Ireland" initiative cannot be ruled out, and there are still scattered efforts for unification to this day.
Peter, this may explain your very astute and reasonable speculation.