Just to be clear: The case I make for a referendum in the Republic on the EU UK trade deal is primarily a political one, based on the changed relationship between Ireland and N. Ireland post Brexit Withdrawal and Trade deals and how this is different from the relationship which existed prior to and post the signing of the Good Friday Agreement.

Not being a constitutional legal scholar I cannot speak to whether there will be a technical legal requirement for such a referendum: That is an issue which may ultimately have to be decided by the courts if a legal challenge is taken to any government decision to ratify the deal without a referendum.

The legal question at issue will probably be whether the UK government had the right, under the Good Friday Agreement - which is an international Treaty lodged with the United Nations - to take N. Ireland out of the EU against the expressed will of the majority there.

As the Good Friday Agreement expresses the need for a referendum to effect a change in the constitutional status of N. Ireland specifically in the context of any move towards a united Ireland, it is quite possible that a legal challenge on that basis will fail.

But there is a second basis for a legal challenge, and that is that the people of Ireland approved the removal of articles 2 and 3 from our constitution (our territorial claim to N. Ireland) specifically in the context of the "equality of esteem" provisions of the Good Friday Agreement, and the fact that the EU membership of both parties guaranteed "an ever closer Union" and reduced significance of any border or other differences between the two states.

The Irish people could justifiably feel cheated that Brexit has removed the basis on which they gave up their territorial claim to N. Ireland and replaced a gradual convergence with the promise of ever greater divergence between the UK and EU, and hence between N. Ireland and Ireland.

The UK government could mitigate this grievance by offering to hold a referendum on a united Ireland, under the terms of the Good Friday agreement, but this is somewhat beside the point. The Irish people didn't vote for a united Ireland when they approved the Good Friday Agreement in 1998, but for a peace process which recognised the status quo (of N. Ireland as part of the UK) in return for a promise of equality of esteem for Irish nationalists and ever greater convergence between N. Ireland and Ireland.

It is doubtful whether a majority in N. Ireland would vote for a united Ireland now, and even in the Republic a majority might only vote for it in the context of a comprehensive peace deal which specified in great detail how the transition would be managed, how a united Ireland would be governed, and how the costs would be funded.

Very few in Ireland want to take over a divided society, a failed economy, and the possibility of widespread violence in the absence of an agreed plan as to how these challenges and difficulties would be overcome. The consensus is probably that it is best "to let sleeping dogs lie" until such time as Brexit has been fully played out in perhaps 10 years time, the constitutional future of Scotland has been decided, and a clear majority for a united Ireland exists in N. Ireland.

This sort of long term thinking and planning may not fit well with short term media narratives and political imperatives, but is essential if any transition to a united Ireland is to be a peaceful and mutually prosperous one.

Index of Frank's Diaries