Next month, the Irish and British people should be celebrating the 20th anniversary of the Good Friday Agreement. The agreement serves as the cornerstone of the power-sharing deal between Northern Ireland’s unionists and nationalists that helped bring an end to years of violence. It has cemented a long-term constitutional settlement between the United Kingdom and Ireland, in which both states agree that the people of Northern Ireland are free to choose their own destiny. There won’t be any Happy Birthday party this year, however. The power-sharing arrangement that governs the North is on hold, and some prominent British politicians are suggesting that the deal ought to be abandoned altogether.

The Good Friday Agreement faces real internal challenges. First, the center has fallen out of Northern Irish politics. The more moderate Ulster Unionist Party and Social Democratic and Labour Party that were at the center of the original peace deal have been displaced by their more intransigent respective unionist and nationalist rivals, the Democratic Unionist Party and Sinn Fein. Meanwhile, the smaller cross-community parties that helped cement the initial deal have largely disappeared. The result is that hard-liners on both sides now dominate the Northern Irish power-sharing executive envisaged by the agreement.

For a long time, this worked better than expected. Both sides saw pragmatic benefits to cooperation and were led by people with experience and clout such as Martin McGuinness. In 2017, however, a scandal over a renewable energy scheme that went massively overbudget led Sinn Fein to withdraw from a power-sharing executive that depends on participation from both sides. Now, the leadership of each wing is weaker, and it is the Democratic Unionist Party that is being intransigent. It refuses to return to power sharing because of a controversy over official recognition of the Irish (Gaelic) language, which its supporters see as a big concession to Irish nationalism.

Distrust between the two sides is compounded by the British government’s reliance on Democratic Unionist support in Parliament. Many nationalists suspect that the unionists prefer a situation of uncertainty, where they can shape British government policy on Northern Ireland, to a situation of stability, where they would have to reach compromises with nationalists.                                     

Under slightly better political circumstances, both sides could reach a deal on power sharing again. The harder political challenge comes from a much broader change to British politics that was never envisaged by negotiators—namely, that the United Kingdom decided to leave the European Union.


The surface symptoms of Northern Ireland’s Brexit problem are a series of recent statements from British politicians disparaging the Good Friday Agreement. The right-leaning Labour MP Kate Hoey has said that the United Kingdom needs to take a “cold rational look” at the agreement. Daniel Hannan, an influential Conservative and member of the European Parliament, has complained that the deal is treated “in quasi-religious terms,” even though it is a “bribe” to hard-liners on both sides, while former Northern Ireland Secretary Owen Paterson says that the treaty has “outlived its use.” These statements are not all that worrying or surprising in themselves. The politicians who are making them are all hard-line Euroskeptics, who fear that political disagreement over the border between Northern Ireland and the Republic of Ireland might make it tougher to follow through on Brexit. Their comments are, however, symptoms of a deeper disorder. 

The political deal at the heart of the Good Friday Agreement was deliberately crafted to be ambiguous. Nationalists want Northern Ireland to be part of a united Ireland, while unionists want Northern Ireland to remain part of the United Kingdom. The agreement sidesteps these clashing aspirations by recognizing both goals as legitimate while indefinitely deferring the question of which side will win. The agreement states that Northern Ireland will remain part of the United Kingdom until and unless a majority votes otherwise. At that point, neither the United Kingdom nor Ireland will stand in the way of Northern Ireland’s aspirations. In the meantime, the people of Northern Ireland can choose to identify as either Irish or British as they like and are entitled to citizenship in both countries.

The political deal at the heart of the Good Friday Agreement was deliberately crafted to be ambiguous.

What this ambiguity smoothed over was that the two sides to the conflict placed different and incompatible bets on the future. Unionists gambled that the nationalist minority would become reconciled to life in the United Kingdom over time and would not want to join the Republic even if it became a numerical majority. Nationalists bet that increased ties between the Republic and the North would gradually change the facts on the ground, making the unification of the island of Ireland more likely. The two governments didn’t care as much about who won: both wanted above all to see the conflict go away. Now, however, Brexit exposes the contradictions between the unionist and nationalist gambles. Depending on the precise circumstances under which the United Kingdom leaves the EU, nationalists or unionists will be in a far stronger position to gimmick the long-term odds in their favor.

BritishPrime Minister Theresa May speaks outside Stormont House, in Belfast, Northern Ireland, February 2018.
BritishPrime Minister Theresa May speaks outside Stormont House, in Belfast, Northern Ireland, February 2018.
Clodagh Kilcoyne / REUTERS


The European Union has made it clear that it expects legal certainty and wants Northern Ireland to stay part of the EU’s Customs Union—the arrangement under which goods can easily pass over the borders of EU nation-states, while the EU maintains a common frontier against third countries—alongside the Republic of Ireland, no matter what happens to the rest of the United Kingdom. This means that there are three possible outcomes.

First, Northern Ireland could stay in the Customs Union, while the rest of the United Kingdom leaves it. This would mean that Northern Ireland’s economy would become more tightly entwined with the Republic’s, benefiting the nationalists. Second, the European Union could back down, accepting a hard border between Northern Ireland and the Republic. Here, the unionists would win, although at the cost of an increased risk of violence from angry Irish nationalists. Finally, the entire United Kingdom could remain in the Customs Union and perhaps the Single Market, which allows goods to be sold across the European Union without having to comply with a multitude of different national regulations. This option would maintain the status quo for both nationalists and unionists, at the cost of watering down Brexit and angering pro-Brexit politicians and voters, perhaps leading to the downfall of the current government led by Prime Minister Theresa May.

This is why some pro-Brexit politicians are denouncing the Good Friday Agreement. They fear that the need to placate both nationalists and unionists will lead to the United Kingdom remaining in the Customs Union, which they view as an unacceptable “Brexit lite.” It also explains why others, such as hard-line Conservative MP Jacob Rees-Mogg, who may become the next leader of his party, are deploring the “irresponsible, vote-chasing immaturity” of the Irish government and complaining about the EU’s “clear disregard” of the Good Friday Agreement. Rees-Mogg wants the EU and Ireland to back down, leaving Northern nationalists isolated so that British negotiators can adopt a harder negotiating position without leaving their backs exposed.

Unfortunately, there is no obvious solution that would both be acceptable to the United Kingdom and preserve the balance of power among the communities within Northern Ireland. The British government and the European Union seemingly reached a broad agreement on the border issue after difficult negotiations late last year, but this too was based on a fudge, in which both sides agreed that they would revert to a “backstop” arrangement if no better deal could be reached.

The EU interpreted this backstop as implying that Northern Ireland would stay in the EU’s Single Market or Customs Union. The United Kingdom disagreed and is still holding on to the hope that new technologies or some other creative solution will allow them to avoid hard choices, by magically both having a border and not having it at the same time. No one but British negotiators hold out any real hope that this could work, and it is not clear that British officials believe in it privately either. The British official charged with finding a solution just announced on March 26 that he was leaving his job.

The United Kingdom and the EU are now starting detailed negotiations, and the EU has made it clear that continued ambiguity isn’t good enough. Although the intergovernmental parts of the EU rest on state-to-state negotiations and compromises, the Customs Union and the Single Market both involve the detailed application of strict regulatory frameworks under shared regulatory arrangements. The EU furthermore has a strong bargaining position and intends to use it.

The United Kingdom has repeatedly tried to carve the Irish border question out of the larger negotiations so that it can reach a deal on the other questions that it cares about. This isn’t working. European Council President Donald Tusk has insisted that EU negotiators will show solidarity with Ireland and will press for the resolution of the Irish border question before serious negotiations on other issues. Since the United Kingdom is supposed to leave the EU in March 2019, this doesn’t leave much time to reach an agreement.


It is not clear who will win the standoff. If Northern Ireland stayed in the Customs Union while the rest of the United Kingdom left, unionists would be very unhappy. If they accepted it at all, it would only be on the basis of extensive concessions designed to reassure them that the union with the rest of the United Kingdom was still strong. It is far from clear that nationalists would assent to such concessions, likely leading to further standoffs and internal tension. Still, that would probably be better than a full EU pullout for Northern Ireland, which would almost certainly lead to the reimposition of a hard border. Republican intransigents haven’t gone away and have mounted occasional terrorist attacks. If the border came back, other nationalists might start to support them, returning Northern Ireland to the bad old days before the agreement was signed.

The best outcome for the Good Friday Agreement would be if the United Kingdom agreed to remain in the Customs Union and Single Market. If this happened, the ambiguities would be restored, allowing both the unionists and the nationalists to return to the usual bickering and gradual wars of position. The agreement would be harder to manage with one country inside the EU and the other outside, but far from impossible.

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  • HENRY FARRELL is Professor of Political Science and International Affairs at George Washington University’s Elliott School of International Affairs.
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