Many parts of the agreement rested on the fact that both the U.K. and the Republic of Ireland belonged to the European Union and, thus, shared a common political and economic framework. The U.K.’s decision to leave the E.U. — called Brexit — could undermine important parts of the agreement.
Agreeing to leave Northern Ireland bi-national and co-sovereign
The agreement’s main contribution was the creation of the Northern Ireland Assembly, a parliamentary body that guarantees a voice for both of Northern Ireland’s main communities.
The agreement also created intergovernmental councils in which government officials work closely with other regional governments in the U.K. and with the Republic of Ireland. These councils allow nationalists and unionists to ensure connections to Ireland and the U.K., respectively. And the agreement allowed residents of Northern Ireland to identify as British, Irish or both, and to claim citizenship in one or both countries.
Although the agreement didn’t set out to foster economic integration, the absence of war and common membership in the E.U. made it possible. Today, people, goods and services move freely across the border between the Republic of Ireland and Northern Ireland. The only indication that you’ve crossed the border is a change in the background color of signs — green in Ireland and blue in Northern Ireland.
According to political scientist Brendan O’Leary, the agreement “made Ireland bi-national,” providing “imaginative elements of co-sovereignty.” As such, even though the constitutional question at the heart of the conflict — should Northern Ireland be part of Ireland or the U. K.? — has not been definitively answered, the agreement meant the incompatible identities of unionist and nationalist could be, if not reconciled, at least balanced.
Brexit could upend these delicate compromises
Brexit calls all these relationships into question. The most pressing issue is the border. When Britain leaves the E.U., the E.U.’s legal boundaries will change. How the border changes is ultimately up to British and E.U. negotiators, but the two largest parties inside Northern Ireland — Sinn Fein and the Democratic Unionist Party (DUP) — don’t agree on what the border should look like.
The DUP prefers a “hard border.” This would mean that the border between the Republic and Northern Ireland would look more like international borders outside the E.U., with border security, passport controls and customs.
Sinn Fein favors a soft border. To preserve the current freedom of movement between the two countries, Sinn Fein would like to see the formal border defined as existing in the Irish Sea. That way, travelers and goods from the E.U. would pass through customs and border control when entering London but not when moving from Dublin to Belfast.
Nationalists oppose a hard border because it would undermine (in practice) their right to claim Irish citizenship and travel across unimpeded. Unionists oppose a soft border because they believe it would not only separate them from the U.K. but also impose a de facto unification with Ireland.
Rights, goods, and institutions
Brexit may also nullify Britain’s membership in the European Convention on Human Rights. The ECHR is important because it guarantees a common set of rights for Catholics and Protestants in Northern Ireland’s new legal structures. This is no mean feat. For much of Northern Ireland’s history, Catholics were systematically discriminated against by Unionist leaders. For instance, Catholics complained that Protestants were given better access to publicly subsidized housing. During the Troubles, allegations of discrimination increased. In 1972, for example, the U.K. government created Diplock courts for those accused of terrorist offenses, usually Catholics. Defendants lost their rights to a jury trial; their cases were heard by a single judge with lower standards of evidence.
Having ECHR’s human rights framework was critical to Catholic support of the agreement. Without it, nationalists may withdraw their support for the agreement.
Brexit may also upend the economic integration between Ireland and Northern Ireland. For example, many popular brands of whiskey, butter, cheese and milk cross the border several times before the final product is ready for market. A hard border could make cross-border production more difficult and lead to higher prices.
Unionists’ and nationalists’ differing attitudes toward Brexit are already straining relations. Although a majority of Northern Ireland voted to remain in the E.U., 85 percent of nationalists voted to stay — 40 percent of unionists did. In fact, the DUP was the only party in Northern Ireland to campaign in favor of Brexit. Like Scotland, which also voted against Brexit, Northern Ireland will be dragged out of the E.U. against its will, further antagonizing nationalists, who dispute the legitimacy of Northern Ireland’s inclusion in the U.K.
Perhaps most important, Brexit has the potential to wreck Northern Ireland’s power-sharing institutions. After Prime Minister Theresa May called snap elections last June, the Conservatives lost their majority in the British Parliament and, as a result, formed a “confidence and supply agreement” with the DUP to stay in power. Although the DUP never signed the Good Friday Agreement and holds only a narrow majority in Northern Ireland, it now holds the balance of power in the British Parliament. That makes it impossible for the British government to be a neutral arbiter in disputes between the DUP and other parties in Northern Ireland.
The Northern Ireland Assembly was suspended in January, and the two parties have been unable to form a government since. Without a functional government, Northern Ireland can’t articulate its interests in Brexit negotiations. It also cannot accomplish the basic tasks of governing and, thus, may soon find itself under direct rule from the British government — a potentially perilous situation, given that sharing power in the assembly was critical to winning nationalist support for the agreement.
Brexit will profoundly change the agreement and could weaken the willingness of some parties to support it. The agreement may survive, but its parties will have to reimagine it for a post-Brexit world.
Kimberly Cowell-Meyers is an assistant professor of government in the School of Public Affairs at American University.
Carolyn Gallaher is an associate professor in the School of International Service at American University.