Before and during the EU referendum campaign, it was claimed that Brexit would damage the Union.  Some said that a Leave vote would make Scottish independence more likely.  There is no yet evidence that it has done so, and quite a bit to the contrary.  It was also argued that such an outcome could destabilise Northern Ireland.  But to date, the province has taken the result in its stride.  So far, so good.  However, Remainers and Leavers alike were perhaps searching for possible repercussions in the wrong place.  They should have been looking not within our frontiers, but to just outside them – to the only country in Europe with which we share a land border.

Brexit’s consequences for that country, Ireland, are thus also consequences for us.  These break down into three broad categories.  The first are a mass of concerns arising from proximity or language or both.  On the former front, for example, there is the question of how fishing rights will be allocated after Britain leaves.  On the latter, there is the matter of what will happen, say, to joint projects between Irish and British universities, in these two English-speaking countries, once one is a member of the EU and one is not.

The second set of issues are directly related to the border itself.  Like the first basket of problems, they are not impossible to solve.  Neither Britain nor Ireland want to put in place the hard border that has never really existed – not even during the Troubles.  As our columnist, Daniel Hannan, has pointed out, the border “is criss-crossed by a latticework of lanes”, most of them dating back to the nineteenth century or further.  It is possible to imagine that the two countries will build on the agreement they signed in 2011 to develop border management systems and to share data.  “There is going to be more focus on the perimeter,” Frances Fitzgerald, Ireland’s Deputy Prime Minister, said recently that “we are now the border effectively for the EU.”

The final issue is more complex.  Britain is Ireland’s largest export market within the EU.  Indeed, the former is the latter’s biggest trading partner.  A third of Irish agri-food exports come here.  These include half Ireland’s beef exports.  Bertie Ahern and John Bruton, two former Taoiseachs, ran through some of the figures recently when they gave evidence to a Lords Select Committee.  Irish exporters are already feeling the effects of the fall in sterling: five mushroom farms have already closed.

Admittedly, what one loses on exchange rate swings one gains on their roundabouts.  It can be argued that the pound has been over-valued, that this has benefited Ireland and other exporters to Britain, and that a correction is now taking place which they must take on the chin.  But it is not at all easy to dismiss concerns about the future of customs.  Daniel has floated maintaining aspects of the customs union with Ireland.  It is possible that this is precisely the kind of a la carte solution which Theresa May will favour as part of her “bespoke” Brexit deal.  None the less, reaching agreement, on customs or anything else, will not be a matter that Britain and Ireland can negotiate between themselves alone.  The former will be acting alone; the latter as one state in 27.

This is the crux of the matter.  In one sense, the two countries are about as close as it is possible for separate states to be.  Their citizens are linked by shared history.  They enjoy a common travel area.  Indeed, citizens of the Irish Republic are not treated by Britain as aliens, and vice-versa.  But in another sense, that history also keeps the two countries at a certain distance: a glance at it will explain why Ireland is an independent state in the first place (and why Northern Ireland is still part of the United Kingdom).

For some people in Ireland, EU membership not only gave the country an opportunity to slip out from Britain’s shadow, but offered Britain itself a chance to escape from its own history as a fellow member.  Bruton began his evidence to the committee by evoking the memory of how both countries joined the EU on the same day.  Common EU membership played a vague but powerful part in bringing Britain and Ireland closer together, and thus finding a solution to Northern Ireland’s troubles.  The prospect of a self-governing Britain, unrestrained by EU membership, stirs unhappy memories in Ireland.  Even if it did not, the latter will soon be in the peculiar situation of being the only mainly English-speaking country in the EU.  What will that mean for EU immigration into Ireland?

What for that matter will it mean for the common travel area, if Britain introduces work permits for EU nationals?  The questions arising from Brexit are complex, but the context is straightforward.  The UK is set to leave the EU at more or less the same moment when the latter’s role in relation to Ireland is itself changing.  News that the country became a net contributor to the EU in 2014 became public almost as votes in Britain’s referendum were being cast.  The Commission is seeking to bust up Apple’s tax deal with Ireland: more investigations will follow.

The country is moving rapidly from occupying a similar place within the EU to the olive belt states, as a net beneficiary, to one more like that of other northern European countries, as it becomes a net contributor.  Our Government can do nothing much about this.  But it can give more thought to Ireland’s position than it seems to have done to date.  After all, our close relationship to it, economic and political, should render it a useful ally in the negotiations to come.  A would-be punitive settlement for Britain is not in Ireland’s interest – or anyone else’s, as Enda Kenny has pointed out.  And both countries can share a common aim of carving out a post-Brexit settlement between them that preserves as much continuity as possible with the present dispensation.

To maximise the chances of obtaining it, Theresa May, David Davis and James Brokenshire in particular should make as much use of the present institutional framework as possible – that’s to say, the British Irish Council and, in particular, the British-Irish Intergovernmental conference, in which Ministers in the two governments meet face to face.  The Government will need to keep the DUP and UUP onside.  In the past, there has been an Irish question and at present there is, we read, a British one.  Now there is a Brexit question too to keep both countries busy.