And the answer to that question is still problematical among sections of the Roman Catholic majority.
For much of our modern history, many Roman Catholic nationalists rejected the notion that ordinary Irish Protestants (by which I do not mean the Anglo-Irish aristocracy) were as Irish as the Roman Catholic majority.
MacDonogh believes, with good reason, that a reactionary Roman Catholic nationalism -- as distinct from the pluralist Irish republicanism to which MacDonogh, a Southern Protestant, subscribes -- bears much of the responsibility for alienating Irish Protestants from the republican ideal.
This kind of tribalism thrives in surprising places.
In a recent book, David McWilliams recorded an anecdote showing that Seanie FitzPatrick saw himself not just as a profiteering capitalist but as some kind of Catholic nationalist putting uppity Prods in their place.
Sadly, this is not the sole example of Roman Catholic capitalists presenting their profiteering as patriotism.
The story of how ordinary Irish Protestants -- like Obama's ancestors -- were marginalised from mainstream political life is only one of the themes in MacDonogh's riveting reconstruction of Barack Obama's Offaly ancestors. But it is the one which matters more to us in the long run on this island.
But first, in case you missed the other many good reviews of this book, let me give you a brief synopsis of MacDonogh's research into the President's Irish roots. Obama's genes, on his mother's side, go all the way back to the Kearneys of Moneygall, Co Offaly, a modest family of Southern Irish Protestant artisans, wigmakers and weavers -- nothing like the nationalist stereotype which pretends that most Irish Protestants were landlords who lived in Big Houses.
The Kearney exodus from Co Offaly to Ohio started just after the 1798 Rebellion, in which Protestant radicals played a leading role. Some time in 1780, Thomas Kearney, a member of the Church of Ireland, emigrated from Co Offaly, arrived in Baltimore, Maryland, and married a Methodist, Sarah Baxley, thus giving us genetic proof, by way of a written record, of President Obama's maternal Irish roots.
Like it or lump it, President Obama is literally a bit of a black Protestant. As the term "black Protestant", like the abusive term "souper", was common in my childhood, and still lingers in our lexicon, I want to say what it meant to my mother, a member of the rural Roscommon Roman Catholic cottier class.
My mother had not a sectarian bone in her body. Indeed, she insisted that we take off our school caps when we met the local Church of Ireland minister. But, like her Roman Catholic neighbours in Roscommon, she reflexively applied the terms "black Protestant" and "souper" not so much to Protestants who lived on our road, but to Protestants as she had been taught to regard them historically.
The purpose of tribal terms like " black Protestant" and "souper" was to put a question mark over the Irishness of Irish Protestants. As this is one of the major themes of MacDonogh's book, let me add my tuppence worth by trying to pin down concretely what "black Protestant" and "souper" meant in Catholic nationalist discourse.
The phrase "black Protestant" seemed to have class as well as sectarian connotations. It was never applied to the Anglo-Irish aristocracy, possibly because most rural Roman Catholics assumed the Anglo-Irish believed in nothing much except horses and hounds. As I recall, it was mostly low church Irish Protestants, particularly Methodists, who attracted the term "black Protestant".
Methodists and poorer Protestants earned the jibe if they seemed too diligent in discharging their religious duties, were not emollient enough in their dealings with Roman Catholics, and not sufficiently humble in keeping the head down. Roman Catholic tribalists regarded such Protestants much as Southern white trash saw uppity blacks.
The term "souper" is also more subtle than it looks. In 1984, when President Ronald Reagan visited his ancestral home in the Tipperary village of Ballyporeen, the international media -- and indeed some Irish hacks -- were baffled by a slogan whitewashed on one of the roads: "Reagan is a Souper."
The crude explanation was that calling Reagan a "souper" meant his ancestors were Roman Catholics who "took the soup" -- that is, converted to Protestantism for food during the Famine. But if you asked my mother she would have given a more complex reading, like this: "Reagan is not the proper spelling of Regan. That means the Regans must have changed the spelling some time -- probably when they reneged on their Roman Catholic religion. The new spelling signals that they are no longer Roman Catholics so nobody is embarrassed."
MacDonogh's brilliant book puts historical flesh on how these false folk images of Irish Protestants were formed. Like Fergus Whelan in Dissent into Treason, MacDonogh argues that the rise of a narrow Roman Catholic nationalism -- in which Daniel O'Connell played a major part -- steadily alienated Southern Irish Protestants from the republican and proto-socialist ideals for which so many of them had fought and died in 1798.
After the Famine, the rise of a reactionary Roman Catholicism pushed Irish Protestants out of the national pantheon. The teaching of Irish history played down the patriotism of ordinary Protestants so that they (in MacDonogh's phrase) "conformed to the character of an odious absentee landlord bogeyman".
MacDonogh adds that the "gaping wound of the Famine gave rise to fierce simplicities, forging the mythical image of Irish identity that has been largely sustained through to the present generation". And I would argue that these mythical images formed the mindset which led to the murders of Protestants in the Bandon Valley in 1922, a story told movingly by Sean O Mealoid in the RTE film, Cork's Bloody Secret.
The conflation of ordinary Irish Protestants with the Anglo-Irish landlord class meant that thousands of patriotic Irish Protestants, like Obama's ancestors, were seen as somehow less Irish than their Roman Catholic neighbours. As MacDonogh says, "Irish Protestants such as the Kearneys came to be regarded as foreigners in their own country, denoted in Irish as gall."
This process took many practical forms. MacDonogh records a meeting in Moneygall in January 1881, where the parish priest recited a verse calling for the word "gall"(meaning "foreigner") to be removed from the name Moneygall.
But, of course, the Kearneys loved their country as much if not more than their Roman Catholic neighbours -- as witnessed by the care they took, long after emigrating to America, to record their roots in Moneygall.
All of the above only scratches the surface of this superb book. But I shall be back for more. Next time I might actually get as far as America.
'Barack Obama -- The Road from Moneygall', by Stephen MacDonogh, is published by Brandon PressSIC: II