IN the summer of 1971, a fun fair sprang up on the banks of the River Lagan in south Belfast, sharing space with an exhibition centre on a 37-acre site in the Botanic Gardens. “Ulster 71” had been years in the planning and the Stormont government wanted it to showcase the best Northern Ireland had to offer in its 50th year in existence.

Outside the perimeter of the site, the Troubles raged. Cynics nicknamed the Botanic Gardens attraction “Explo 71”. Opponents denounced it as an exercise in “official amnesia” deliberately forgetting Northern Ireland’s track record on “unemployment, exploitation, forced migration and sectarian hatred”.

The Troubles put off many of the visitors from elsewhere in the UK that Stormont had been hoping to attract, but the locals seemed undeterred. By the time the exhibition stands were dismantled it was claimed half-a-million people – a third of the population – had visited.

Fast forward 50 years and preparations are under way for the 2021 centenary of the foundation of the Northern Ireland state. The conflict ignited in 1969 has – largely – been transformed into a political rather than a violent quarrel. But the plans for the commemoration of the birth of the modern UK are beset by uncertainty of a different kind.

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The Orange Order has signalled its intention to mark the centenary with fireworks displays and (Covid allowing) a mass parade in May, around the date of the first session of the Northern Ireland parliament.

The UK Government’s official planning document is more restrained. It envisages a debate on the centenary’s significance at Belfast’s Queen’s University, a commemoration at Belfast City Hall and a service of reflection and reconciliation somewhere in Britain.

Attempts will be made to involve young people, the creative sector and Northern Ireland’s Diaspora. But, as with all plans being hatched in these times of pandemic, every element in will have to be Covid-proofed.

A forum has been set up to try to agree on the shape of any commemorations. However, shortly after Boris Johnson unveiled the forum, both the main Irish nationalist parties, Sinn Fein and the SDLP, made it clear they would not participate. The Sinn Fein Deputy First Minister Michelle O’Neill said she saw nothing to celebrate in the partition of Ireland. The nationalist-dominated Derry and Strabane Council voted to play no part in the centenary plans.

Some unionists expressed annoyance at the nationalist boycott of the preparations, pointing out the Queen participated in the Irish government’s ceremonies marking the centenary of the 1916 Easter rising against British rule. However, nationalist disdain for any UK approved telling of the story of Northern Ireland is hardly surprising. What was perhaps more remarkable was the almost complete absence of civic Catholic participation in the official centenary forum.

The UK would like to keep any commemorations as soft focus as possible, concentrating on the contribution Ulster people have made to sport, science and the arts. There’s also likely to be an emphasis on 1921 as the starting point for the wider union – a point often forgotten in Britain where the central argument about the future of the UK tends to pivot around Scotland’s intentions.

Come May, however, the UK’s “softly softly” approach is likely to be lost in a harder-edged debate about Northern Ireland’s divided history. The obvious question will be posed regarding how many more anniversaries the often troubled state is likely to be able to mark.

At Stormont, unionists have lost their majority, while a growing Catholic population undermines the logic of the convenient line of partition drawn across the map of Ireland back in the 1920s.

Despite that, nationalists haven’t yet overhauled unionists at recent elections. Instead it looks like the immediate future will lie in the hands of centre-ground voters and their representatives, who by their nature have tired of the traditional polarisation of local politics.

However, 2021 will not simply usher in Northern Ireland’s centenary commemorations. It will also mark the first year of the state’s projected “half in half out” status within the economic unions of both the UK and the EU. At the time of writing, it’s impossible to know for sure how the practical application of the Brexit protocol will impact on daily lives and livelihoods people and what the political fallout might be.

Optimists reckon the territory’s special access to the EU single market will provide opportunities which can be harnessed for economic growth. Pessimists fear vital supplies of food and medicine will face disruption and that some English manufacturers could decide exporting their products to Northern Ireland isn’t worth the hassle of all the extra paperwork.

As of now, it looks like the prospect of a hard economic border across the island of Ireland has receded. But the political ramifications of a new economic border down the Irish Sea remain difficult to predict. Could greater economic integration with the EU make the prospect of a united Ireland more attractive to floating centre-ground voters? Or might they conclude they have already had more than enough uncertainty to deal with?

Various pollsters have tried to ascertain the impact of Brexit on the intentions of voters in any future border poll. But it seems fair to assume those voters won’t themselves be sure of exactly how they will respond to life under the Protocol until it becomes a lived reality.

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Brexit, of course, isn’t the only variable. After the SNP first won a majority in Scotland, the then Sinn Fein president Gerry Adams told me he thought developments there could turn out to be far more momentous for the situation in Ireland than had previously been imagined.

Last year’s heated debates over Brexit revealed some English political activists took a transactional view not only to the UK’s membership of the EU, but also to the bonds between the constituent parts of the UK. Although this may recede once Brexit is a fully fledged reality, one wonders how English voters might regard Northern Ireland in the event of any future pro-independence vote in Scotland.

Apart from Brexit and the possibility of Scottish independence, other determinants are certain to weigh on Northern Ireland voters’ minds should a border poll become a real prospect – issues such as the NHS, continuity of pensions and other benefits and currency.

Whatever the variables involved in determining the timing and context of any future border poll, this much is clear. Nationalists may boycott next year’s centenary commemorations, but they will certainly take an active proselytising role should any future British Secretary of State decide the time is right to put the continued existence of the Northern Ireland state to the test.

Mark Devenport is a journalist and broadcaster analysing Stormont politics, Brexit, the response to Covid-19, British-Irish relations and conflict resolution