How likely is a united Ireland and when could it happen?

Sinn Fein leader calls for immediate establishment of citizens’ assembly to discuss ‘how we transition’ to a united Ireland

Sinn Féin deputy leader Michelle O'Neill with party leader Mary Lou McDonald
Sinn Féin deputy leader Michelle O'Neill is Northern Ireland's first Republican first minister
(Image credit: Charles McQuillan/Getty Images)

Sinn Fein’s leader in Ireland, Mary Lou McDonald, has claimed a border poll on unification will take place “this decade”, after the party cemented its status as the leading political force in Northern Ireland following huge gains in local elections.

The Irish republicans had been tipped to finish a strong first place in council elections on 18 May, overtaking the Democratic Unionist Party (DUP) along the way, but even their “wildest hopes were eclipsed as the weekend’s results built to a crescendo over a marathon two-day count”, said Politico.

Sinn Fein, which was already the largest party at Stormont following the Northern Ireland Assembly elections last year, now has 144 council members, eclipsing the DUP’s 122.

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Taken along with the results of the 2021 census, which revealed that Catholics outnumber Protestants in Northern Ireland for the first time, McDonald told the Irish Times a referendum on Irish unification could take place within 10 years.

‘Ticking clock’

According to the latest census data, some 45.7% of Northern Ireland’s population are now classed Catholic or from a Catholic background, compared with 43.5% from Protestant or other Christian backgrounds. At the time of partition in 1921 Protestants made up about two-thirds of the population of Northern Ireland.

For decades, this Protestant majority helped “safeguard” the nation’s position in the UK, said LBC. “But higher birth rates amongst Catholics has gradually closed the gap.”

Duncan Morrow, a politics professor at Ulster University, predicted that the shift would increase calls for a referendum on Irish unity. “It’s a ticking clock,” he said.

Border poll

As things stand, the Good Friday Agreement means that a border poll can be held at any time. A vote could be called by the Northern Ireland secretary of state if it “appeared likely” that a majority of those voting “would express a wish” for Northern Ireland to form part of a united Ireland.

The Irish Republic would also have to hold a referendum, with the latest Ipsos Mori polls suggesting there is a majority of more than four to one south of the border in favour of unity.

Just as in the run-up to the National Assembly election last May, Sinn Féin made very little mention of a border poll while campaigning for the local elections, instead focusing on bread-and-butter issues. However, the party’s Stormont manifesto outlined its commitment to a referendum on Irish unity and called on the British and Irish governments to set a date for a border poll. McDonald has previously said planning for a unity referendum would come within a “five-year framework”, but following the party’s success in the North’s council elections has now called for the immediate establishment of a citizens’ assembly to discuss “how we transition” to a united Ireland.

Even the son of DUP founder Ian Paisley has admitted that the prospect of a united Ireland is becoming more likely. Speaking at the Seanad last year, the Rev Kyle Paisley said that “my heart is fixed and can’t be won”, but warned that a “disastrous” Brexit and the trade border between Britain and Northern Ireland had shifted public attitudes.

No majority quite yet

That sentiment appears to have been borne out in the latest annual Life and Times Survey, reported by Politico, which found 45% of people in Northern Ireland now expect to join a united Ireland rather than stay in the UK, compared to only 38% who still think the union with Britain will remain. A huge 63% thought Brexit has made unification more likely in any time frame.

Polls still show support for a united Ireland falls well short of a majority, however. A survey by Lucid Talk last August found “only 41% in a region still trying to overcome a legacy of division would vote for reunification today.” The most recent poll from the ARINS Project published in December 2022 revealed that just 27% of respondents supported Irish unity while 50% said they wanted to stay in the UK.

Fact Check NI said “tracking all major polls since November 2017 reveals no significant trend, up or down, in support for Irish unity.” In March, DUP leader Sir Jeffrey Donaldson told the National Press Club in Washington DC that “there is no evidence of growing support for Northern Ireland leaving the United Kingdom. Indeed, every major poll points in the opposite direction.”

That said, it remains in Sinn Féin's interests to “create the impression that a referendum on Irish unity is imminent”, said David Blevins, senior Ireland correspondent for Sky News.

So “what chance a border poll being button-pressed by the Northern Ireland secretary, as required by the Belfast Agreement?” asked Brendan O’Brien in the Irish Times. “As demanded by Sinn Féin? None. Could you put a timescale on when? No. First, get back to the starting blocks. Get the Assembly, Executive and North-South Ministerial Council up, running and doing the business,” he said.

History suggests the reunification process will take time and should not be rushed, O’Brien concluded, “but if things are done right, this wee island could be on the way to a healthy, happy, unified future.”

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