It’s Anyone’s Guess What Could Happen in Northern Ireland in the Next 12 Weeks

Prime Minister Rishi Sunak of Britain finds himself in an abyss of public disapproval. Few politicians have done less to get there. His unpopularity (his Tory Party now lags the Labour opposition by 21 points) is mostly a result of things that happened before he arrived in office. There was the budgetary incompetence of his short-lived predecessor Liz Truss. There was the untrustworthiness of Boris Johnson, who led Britain out of the European Union after the so-called Brexit referendum.

Now a detail of Brexit that was mismanaged years ago has landed Mr. Sunak in a serious predicament. It stems from the fact that Ireland remains part of the European Union but Northern Ireland no longer is — and yet the two parts of the island are bound by trade and a 25-year-old peace treaty that helped defuse a terrorist conflict between Protestant unionists and Catholics.

Those loose ends were tied up in a little-understood clarification of Brexit called the Northern Ireland protocol, ratified in January 2020. It looked like a mere codicil three years ago; now it looks like a serious diplomatic blunder that could threaten Britain’s territory and the region’s peace.

For almost a year, the Democratic Unionist Party, which favors maintaining Northern Ireland’s ties to the British mainland, has blocked the formation of a regional government and demanded that the Northern Ireland protocol be revised. Last Thursday a deadline passed that will require Mr. Sunak’s government to schedule new elections within 12 weeks.

A new vote opens the way to unguessable outcomes — an uprising in Mr. Sunak’s own party, a move to unite the six Irish counties that are part of the United Kingdom with the 26 controlled by the Irish Republic, even the resumption of the decades of political unrest that roiled Northern Ireland until the end of the last century.

Ireland nearly undid Brexit from the start. It seemed during the 2016 referendum that should Britain “take back control,” as the slogan went, it would be able to set its own rules. Instead, there followed three and a half poisonous years in which the country had to negotiate and quarrel its way out of the European Union. “Brexit means Brexit,” said the Tory prime minister Theresa May, but it turned out Brexit meant different things to different people.

Ms. May promised — too hastily, in retrospect — to honor the 1998 Good Friday peace agreement among Britain, Northern Ireland’s political parties and the Republic of Ireland. One of the main things the agreement did was to bind together the economies of Ireland’s north and south. But adapting that arrangement to a post-Brexit world came at a steep constitutional price for the north. To protect the European single market against smuggling and the transfer of unauthorized goods through Northern Ireland, a customs border would be established between Northern Ireland and Britain. To administer the single market, the European Court of Justice was given authority to interpret E.U. law in Northern Ireland.

This is the core of the grievance that has brought Northern Ireland to the brink of ungovernability. The controversy is often described as a trade dispute in a region torn between two political systems. But that is not right. Politically, Northern Ireland is not torn; it is part of the United Kingdom. And the main problem is not trade; it’s that under the pretext of trade, the European Union is laying claim to a territory that does not belong to it.

There is a lack of reciprocity in the treaty that is reminiscent of 19th-century agreements between European powers and their colonies. Why does Britain have none of the prerogatives on E.U. territory that the European Union claims on British territory? After all, the United Kingdom, too, is a single market, just as vulnerable to smugglers as the European Union, and the protocol does not permit analogous customs checks on goods arriving in Irish ports from continental ones.

The larger gripe with the treaty is the role it accords European Union institutions, particularly the European Court of Justice. Many citizens of Northern Ireland worry that they can now have their laws and social arrangements overruled by E.U. authorities that they had no role in electing or appointing. At the height of the Covid pandemic, the vaccine-strapped European Union tried to use the Northern Ireland protocol to block the flow of vaccines between Ireland and Northern Ireland.

The European Court of Justice proclaims the supremacy of E.U. law over the laws of the various member states. It operates in practice to transfer decision making from national capitals to Brussels. Such actions continue to provoke outrage even in states that belong to the European Union. Britain, it will be remembered, is no longer an E.U. member. And over years of Brexit-related quarrels, the tolerance of Britain’s conservative leaders for international regulatory bodies has waned.

E.U. officials often behave as if they do not realize this. Maros Sefcovic, a Slovak diplomat and European commissioner who has been the European Union’s point man on protocol negotiations, has spoken of British moves to change the Northern Ireland protocol as a “breach of international law.”

But countries leave treaties all the time. If Mr. Sefcovic believes anything that Britain does regarding Northern Ireland threatens international law, then he is laying claim to Britain’s sovereign territory — a part of it, moreover, that was within living memory the home to a sadistic, two-sided terroristic conflict that occasionally rose to the intensity of a civil war. If this really is the view of Britain’s European neighbors regarding the protocol, then it is a matter of increasing urgency that Britain break free of it.

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