So, how will Northern Ireland parties protect our compelling interests after Brexit?Article 50 has been triggered and the countdown to leaving the EU has begun, but local politicians are at sixes and sevens, writes Chris Ryder
Early one sunny Sunday morning in the 1980s, while driving from Dublin to Belfast, I encountered a number of elephants, horses and llamas standing at the side of the main road at the Killeen customs post. They were part of a travelling circus having its documentation checked as it crossed the border.
However, in 1994, the European Economic Area came into force, enabling the free movement of people, goods, services and capital within the European Single Market.
The disappearance of the border in all but constitutional terms brought an end to traditional customs controls and facilitated unimpeded commercial traffic between the two parts of Ireland and the British mainland. It also opened up large chunks of the European mainland to local businesses.
Just as significantly, it brought an end to lucrative smuggling by crime gangs that had long exploited the complex revenue rules to enrich themselves.
But, thanks to the Brexit referendum last year and Britain's decision to leave the EU, the sleeping land border has once again become a major issue.
As the full implications of the vote began to sink in, the Irish Government and pro-EU parties in Northern Ireland, where a clear majority of electors voted to remain in the EU, realised that the structures of trading cooperation and the peace process, carefully crafted over the last 20 years, were now in real peril.
From the outset of this accelerating crisis, the British insisted there would be no return to the hard borders of the past and that it was their aim to maintain a frictionless regime allowing open cross-border activity to prevail.
The Common Travel Area, dating from the 1920s, entitling Irish citizens to settle and travel between the two islands without restriction, would also be maintained, the Government stated.
But these fine words are now being interpreted in Dublin as no more than well-intentioned rhetoric, and have not prevented the government there from ordering each ministry to prepare impact papers about the practical consequences of Brexit in every social, political and economic context.
Officials have even been despatched to the border to scout possible locations for customs checkpoints in the event that the EU imposes customs controls on what will become a land frontier with Britain.
On the eve of the recent Assembly election, James Brokenshire went to Brussels, the powerhouse of the EU, with a shopping-list, as he sees it, in the absence of detailed demands from the local parties, which were pre-occupied with electioneering, rather than policy-making. His intervention was, therefore, little more than a stunt, as Theresa May's triggering of Article 50 yesterday initiated what will be at least two years of grinding exit negotiations.
While in Brussels, Brokenshire purred that he wanted to see Britain's future relationship with the EU redefined, especially with Ireland, which intends to remain within the unique 27-nation, economic, social and political alliance.
He said he approached the coming negotiations from a unique position: we have the same rules, regulations and standards as the rest of the EU.
Which begs the very fundamental question, what, then, is the point of Brexit, when we already fully enjoy all the benefits he set out as desirable outcomes from the looming Brexit process?
The origins of Brexit actually go back to January 1973, when Britain and Ireland first joined the European Common Market. Within a short time, some British MPs, mainly right-wing Conservatives, opposed to it began a campaign of voluble opposition, earning for themselves the designation 'Eurosceptic'.
Their opposition to EU membership was sustained and never wavered over the years. In a bid to finally silence them, David Cameron conceded a referendum last year, a decision that backfired with fundamentally unintended consequences as England and Wales voted to leave and Scotland and Northern Ireland voted to remain.
The DUP, which has always opposed membership, but soaked up every possible subsidy in full, campaigned to leave. It now insists that, as the referendum was a UK-wide one, the clear Remain vote here must be treated as part of the national decision, with a majority voting to leave.
The British Government agrees and is keeping the DUP sweet, so that its MPs will support any tight Brexit votes at Westminster. They have also opposed any demands for special status for Northern Ireland, as suggested by Remainers here and the Dublin government, being included in the final deal.
However, Sinn Fein and the SDLP, both vigorously opposed to Brexit, insist the vote here must be respected. The Dublin government agrees and will ensure that the future status of Northern Ireland is favourably defined during the coming negotiations. So, the DUP will come under pressure to justify opposing EU membership.
Nelson McCausland, who lost his seat, declared he didn't care what the outcome was as long as he was out of Europe.
Others simply welcome the return of the border and see their anti-EU stance as proving their Britishness.
But, as the pro-EU parties and influential business bodies recognise, there are ever more ominous signs that Brexit will have a seriously damaging impact on our already-fragile economy.
A recent survey concluded that nine out of 10 farms, especially dairy farms, which export one-third of their milk over the border, would not be viable without the EU subsidies that currently sustain them.
On the back of that, one of the big banks is already reviewing the status of each of its agricultural borrowers.
In another development, an internationally successful Northern Ireland pharmaceutical manufacturer has established a contingency bridgehead in Dundalk as a hedge against Britain not getting favourable terms to exit the EU.
The doubts and the questions are piling up. It's high time the parties here got to grips with the many implications and what they are going to do to protect our vital economic interests and underpin our future peace and prosperity.
Chris Ryder is a retired Sunday Times journalist