Imagine the Union Flag flying proudly again atop buildings in Ireland, north and south, below the new flag of a United Ireland, a United Ireland that looks a lot more unionist than the Republic.

When Prince Charles visited Cork two years ago, the Union Flag flew high above Brown Thomas, a building erected after its predecessor at 18-21 Patrick Street, Cash’s & Co Ltd, was completely destroyed in the 1920 Burning of Cork.

It felt wrong to see the Union Flag – since the late 17th century it’s only called the Union Jack if it’s flown on a battleship – there, even though I would have thought unremarkable the regular sight on that building of the flag of the European Union, and flags of countries like Canada, the US and France. (It feels wrong too to see the Union Flag in the North, but almost a century of partition has made the North effectively another country.)

I confess I thought immediately of the Waterboys song: “Still he sings an empire song / Still he keeps his navy strong / And he sticks his flag where it ill belongs / Old England is dying”.

And then I thought of how far – pre-Brexit, at least – our relationship with The Old Enemy had progressed, especially since the Good Friday Agreement was signed in 1998, and since the Queen visited Mary McAleese in 2011, and since Michael D returned the compliment three years later.

Last week Sinn Féin leader Mary Lou McDonald predicted a United Ireland will happen within the next decade, and she sought to assure unionists that they would “remain British” if Northern Ireland votes to leave the United Kingdom.  

“We have citizens that are British,” she said. “They are British in a partitioned Ireland and they will be British in a united Ireland.”

Predicting “We can have our referendum, we can win it, and win it well,” Deputy McDonald called on “our unionist brothers and sisters” to become involved in discussions on a united Ireland, saying “we have a huge amount of preparatory work to do for an orderly constitutional transition”.

Our unionist brothers and sisters might have been forgiven for feeling that Mary Lou’s breezy suggestion was not a little on the previous side, but then of course they were never really the (legitimate) target audience.

This was a rallying cry for Sinn Féin, battered as they are from a series of self-inflicted social media-related injuries so foolish that it can almost certainly only be a matter of time before Gerry Adams tweets that he was never in Sinn Fein, either.

It’s got so bad for the Shinners that the announcement must surely be on its way that all official pronouncements will henceforth be issued directly from the Connolly Club in Belfast, published exclusively in An Phoblacht, and signed by P. O’Neill himself.

Hence Mary Lou McDonald’s urging unionists “not to equate the reunification project with threat or loss … it has to be about gain or additionality”.

The next day, Martin Browne, one those new TDs Sinn Féin seems to have won in a Lucky Bag last time out, took to Tipp FM to say SF needs to stop apologising for the actions of the Provisional IRA. “We had an occupied country, a foreign force there. It doesn’t matter whether it was in the 20s, 50s, 70s or 80s it was the same aim, to free our country from an occupying force.”

I was reminded of a recent conversation with someone who messaged me on Twitter asking why I’m “against Sinn Féin”. I replied that I’m very old and can actually remember the atrocities they celebrate.

My correspondent told me they believed the Provos’ terrorist campaign was a war, and “People die in wars”. Opining that “we are occupied still”, they said: “Their loyalists have [the North] littered with Union Jacks and racist marches. It is Ireland.”

I disagreed about the “war”, and added: “The North is a different country, whether we like that or not.” I suggested that any United Ireland cannot just be the Republic with six new counties tacked on.

“It will have to be a new country,” I said, “one which respects the unionist identity, unless you’re seriously proposing just a reversal of the bad old days, this time with a unionist minority in a state they don’t recognise.

“That will mean a whole new state. No more Tricolour, maybe no more Taoiseach. I honestly don’t think too many Shinners have actually thought that one through.”

My friend responded: “It will be back to us. Ireland. Not a new country. Sorry but that’s a fact. We won’t surrender our national identity for their dead ‘empire’. No-one will be chased out of the country. No-one will be hounded as ‘settlers’.”

When I suggested such a course of action might ensure the next Troubles will be fought in Dublin and Cork, they replied, “I’m sure some consideration will be given, i.e. they can choose to hold a British passport, maybe, but otherwise they will be expected to follow the law. Just like us now.”

To be fair, all of this is covered in breathless aspirational tones in Sinn Féin’s own 2016 discussion document “Towards a United Ireland”, but it doesn’t seem to have percolated down to some members.

While, obviously, I don’t suggest one random Sinn Féin supporter speaks for the entire party, I do think that Martin Browne speaks for SF when he says they should not apologise for Provo atrocities. I think Brian Stanley speaks for SF when he tries to tie the cowards who bombed Warrenpoint (and Mullaghmore) to the men who fought the British Empire (at times hand-to-hand) at Kilmichael. I think David Cullinane speaks for SF when he yelps “Up the ’Ra!” at a late-night celebration. I also think former MP Barry McElduff spoke for SF when he wore a loaf of Kingsmill bread on his head on the anniversary of the Kingsmill massacre, when the Provos murdered ten Protestant workers.

The simple truth is that while they lack Mary Lou McDonald’s polish, they all speak for Sinn Féin, at least until the public backlash becomes too much to ignore.

Ignoring the likely economic costs, (up to €30 billion a year, says one TCD study,) a United Ireland will, of necessity, mean a whole new country. That new country will have a new constitution, and it will have a new parliament. Will that be in Dublin? Or Stormont? (My vote is Athlone, where the nuclear bunker is.) We’ll need a new police force, a new army, a new education system, and a new health service. We’ll need a new head of State, too. Sorry, Michael D. You can forget shoving Connie around the green, also, but if we really do have to abandon Amhrán na bhFiann, please can we replace it with something less anodyne than Ireland’s Call?

If we are to have a United Ireland, it will have to be an Ireland where all the children of the nation truly are cherished, and the Union Flag, and all it represents, is respected. If the sight of a flag makes people like me uncomfortable, imagine how uncomfortable it would feel to find yourself suddenly living under the flag of a country you voted against establishing.