Some international boundaries are easy to understand. The Pyrenees form a natural frontier between Spain and France. The Kattegat conveniently separates Sweden and Denmark. While in the past each pair of countries has seen their border shift over time, the current resting place looks very natural.
The boundary between Northern Ireland and the Republic of Ireland does not come in that category. There are few obvious natural boundaries along the route. Donegal is almost cut off from the rest of the Republic of Ireland. Roads snake in and out of the border. Despite or because of its fraught history, it is all rather arbitrary.
The boundary was established in some disorder at the height of the Irish war of independence. As a quick solution, the six most north-easterly counties were retained within the UK on their existing county lines. This made no particular sense on religious grounds, since substantial parts of those six counties were majority Catholic even at that time. The boundary was originally supposed to be reviewed but in the end the review proved too controversial to see through to its conclusion. So the impromptu boundary stuck.
The contrast between the border’s informal origins and its fraught history is stark. After a lot of bloodshed, a way forward for Northern Ireland was brokered through the Good Friday Agreement. Any Brexit settlement is going to need to deal with not just the way in which the EU and the UK wish to establish their ongoing relationship but also to address the hopes and fears of both Northern Irish communities.
The Northern Irish border will be the main land border between Britain and the EU (pedants will note that there will also be EU/UK land borders at Gibraltar and in Cyprus). If Britain is to be outside the customs union, as hardline Leavers are suddenly insisting is essential to honour the Brexit vote, the UK is going to need to put in place a system for monitoring the new trade boundary.
If it fails to do so, it will in substance be giving the EU preferential access over other nations with which the UK trades. It is hard to see how that is consistent with Britain’s Most Favoured Nation obligations under the WTO, under which it must offer all WTO members the terms offered to the otherwise most favoured trading partner. And it needs to do so in a way that is not going to have either the nationalists up in arms because the border has been resurrected or the unionists up in arms because the boundary of the customs union has been moved to the Irish Sea. In each case, “up in arms” has the nasty potential to be literal rather than metaphorical.
The main part of the Brexit agreement is going to require all the élan of Fred Astaire. Those aspects that deal with the Irish border are going to require the skills of Ginger Rogers, who did everything that Fred Astaire did, but in high heels and backwards.
Other better brains than mine are looking at how this might be achieved. For present purposes, I’m going to assume that a solution of some kind will be found. I’m a sunny optimist, you see.
At that point, the UK government will have provided the Scottish government with a route map to dealing with many of the trickier aspects of independence. The Irish border is longer than England’s borders with Scotland and Wales put together. The two English counties and the two Scottish counties that border each other are collectively bigger and emptier than the five Northern Irish counties that border the Republic of Ireland (never mind the Irish counties on the other side of the border).
The practical, legal and technological problems of a border between Scotland and England look far more straightforward than those of a border between Northern Ireland and the Republic of Ireland. A precedent would have been established as to the nature of the enduring relationship between the two sides after they had disentangled.
When the Scottish independence referendum was fought in 2014, one of the biggest weaknesses that Scotland faced was on the practicalities of transition to independence. In a few years’ time the Scottish nationalists may well find themselves with a manual for many aspects, courtesy of Brexit.
For now, the cause of Scottish independence has slipped back slightly from its high water mark. The unionist cause, having been in disarray, has become more organised. After an initial spasm after the EU referendum result, it seems that Scottish opinion is as-you-were so far as independence is concerned.
The SNP, however, has not given up on the cause and it will be waiting for the right moment to declare that a generation is up. When it does, it will be much better prepared on the technicalities than first time around. So Unionists are going to need to be much better prepared than they were last time round on the questions of identity. They don’t look it yet.