The Good Friday Agreement: Foundations of Peace

The Good Friday Agreement, signed on 10 April 1998, stands as one of the most significant peace accords of the late twentieth century. It brought an end to three decades of sectarian violence known as the Troubles, which had claimed over 3,500 lives. The agreement established a power-sharing government in Northern Ireland, cross-border institutions between North and South, and a framework for East–West cooperation between the United Kingdom and the Republic of Ireland. Crucially, it enshrined the principle of consent: Northern Ireland would remain part of the UK unless a majority voted otherwise. The open, invisible border between Northern Ireland and the Republic of Ireland became the physical embodiment of this new era of peace and cooperation.

The agreement was built on the mutual recognition of the two main traditions in Northern Ireland: unionists (who identify as British) and nationalists (who identify as Irish). It created a complex web of political institutions designed to ensure both communities could govern together. At its heart lay the commitment that all parties would use "exclusively peaceful and democratic means" to resolve differences. For more than twenty years, the Good Friday Agreement provided the sturdy constitutional framework that allowed Northern Ireland to move forward, attracting investment, building tourism, and healing deep social wounds.

Brexit: A Shock to the System

The United Kingdom's 2016 referendum vote to leave the European Union fundamentally altered the context in which the Good Friday Agreement operated. Because both the UK and Ireland were EU members, the border between Northern Ireland and the Republic of Ireland was a shared internal EU border, requiring no customs checks or physical infrastructure. Brexit threatened to turn that invisible line into an external frontier of the EU, raising the spectre of a hard border that could revive tensions and disrupt the soft peace that had become routine.

Brexit did not merely challenge trade relations; it struck at the delicate political compromise that underpinned the peace process. Nationalists viewed EU membership as a guarantee of rights and parity of esteem, while many unionists saw Brexit as an opportunity to strengthen the UK's sovereignty. The result was a polarising debate that reopened old divisions. The principle of consent—so carefully protected in the Good Friday Agreement—was now being tested by a UK-wide vote that Northern Ireland had not supported (56% voted Remain).

Article 1 of the Good Friday Agreement states that Northern Ireland's constitutional status can change only with the consent of its people. Yet Brexit, which changed the constitutional relationship between Northern Ireland and the Republic of Ireland (since the latter remained in the EU), was not subject to a specific consent mechanism for Northern Ireland. This created a democratic deficit that critics argued undermined the spirit of the Agreement. The UK government's decision to leave the EU without a tailor-made Northern Ireland solution placed the peace process under unprecedented strain.

The Border: From Invisible to Contentious

No issue illustrates Brexit's impact more vividly than the border between Northern Ireland and Ireland. The Good Friday Agreement made explicit reference to the removal of all security installations along the border. Over the following years, watchtowers were dismantled, checkpoints vanished, and cross-border roads reopened. People and goods moved freely, integrating local economies and communities. The border effectively became an abstract concept for most citizens, allowing families to shop, work, and socialise on either side without hindrance.

Brexit forced negotiators to confront a fundamental question: how could the UK leave the EU's single market and customs union while keeping the Irish border open? From the EU's perspective, an open border meant no customs controls, no phytosanitary inspections, and no regulatory divergence. Without a border in Ireland, the EU required that Northern Ireland remain aligned with its rules. This logical dilemma led to the creation of the Northern Ireland Protocol.

The Northern Ireland Protocol: A Contested Solution

The Protocol, negotiated as part of the Withdrawal Agreement and taking effect on 1 January 2021, aimed to avoid a hard border on the island of Ireland by effectively keeping Northern Ireland in the EU's single market for goods and aligning it with EU customs rules. In practice, this meant that customs checks and regulatory controls were moved to the Irish Sea, creating a de facto border between Great Britain and Northern Ireland. While the Protocol achieved its primary objective of preserving the open land border, it introduced new practical and political problems.

Unionist communities felt that the Protocol placed Northern Ireland in an anomalous position: subject to some EU rules without having a vote on them, and separated from the rest of the UK in trade terms. The Democratic Unionist Party (DUP) withdrew its First Minister from the power-sharing Executive in protest, paralysing the institutions the Good Friday Agreement had created. Nationalists, meanwhile, pointed to the Protocol as evidence that the North's best interests lay in closer alignment with the EU and Ireland.

Political Fallout: Institutions Under Strain

The Good Friday Agreement established three interlocking institutions: the Northern Ireland Assembly (Stormont), the North–South Ministerial Council, and the British–Irish Intergovernmental Conference. Brexit, and particularly the Protocol, placed all three under severe pressure. The Assembly and Executive could not function without cross-community support, and the DUP's boycott meant that Northern Ireland went without a devolved government for two years (from February 2022 to February 2024).

This political vacuum harmed public services, delayed decision-making on health, education, and infrastructure, and deepened community distrust. The absence of a functioning Executive also meant that Northern Ireland had no voice in the negotiations over its own post-Brexit trading arrangements. The democratic deficit that critics had warned about became a reality: decisions affecting Northern Ireland's economy and daily life were being made in London and Brussels without local input.

Community and Identity Rifts

Brexit reignited debates about identity in Northern Ireland, which had been calmed by the Good Friday Agreement's careful balancing of British and Irish identities. Many unionists felt that the Protocol undermined Northern Ireland's place in the UK, while many nationalists saw it as a step toward Irish reunification. These differing perceptions created a new cleavage that complicated efforts to restore power-sharing. The agreement's principle of parity of esteem came under threat as each community interpreted Brexit through its own constitutional lens.

For example, the Protocol's requirement that goods from Great Britain meet EU standards was seen by unionists as a breach of the Acts of Union, while nationalists argued it was a necessary compromise for peace. The very language used to describe the border—either the "Irish Sea border" or the "trade border"—became a proxy for deeper political allegiances. This linguistic divergence highlighted how Brexit had re-politicised an issue that the Good Friday Agreement had successfully depoliticised.

Economic Implications: Trade and Investment

The economic effects of Brexit on Northern Ireland are complex and mixed. On one hand, the Protocol gives Northern Ireland unique dual access: it remains in the UK's internal market and also in the EU's single market for goods. This has attracted some inward investment, as global companies see Northern Ireland as a "gateway" to both markets. On the other hand, businesses face additional bureaucracy when trading with Great Britain, which accounts for around 60% of Northern Ireland's total trade. Customs declarations, veterinary checks, and regulatory divergence have increased costs and delayed deliveries.

Small and medium-sized enterprises, in particular, have struggled with the new frictions. A bakery in County Tyrone that previously sent goods to supermarkets in Glasgow now must complete export health certificates. A farmer exporting cattle to England faces new paperwork. These practical burdens undermine the economic integration that the Good Friday Agreement encouraged. The North–South dimension has also changed: cross-border trade between Northern Ireland and Ireland has increased since Brexit, as businesses on both sides adapt to common EU rules, while trade with Great Britain has declined.

The long-term economic trajectory remains uncertain. The Windsor Framework, agreed in February 2023 between the UK and EU, aimed to smooth the operation of the Protocol by reducing checks on goods destined for Northern Ireland only, and by giving Northern Ireland's institutions a greater voice (the "Stormont Brake"). While the Framework addressed some practical concerns, it did not resolve the fundamental constitutional tension. The continued political instability in Northern Ireland deters long-term investment, as investors value certainty above preferential access.

Social and Community Impact

Brexit has also affected the everyday lives of people in Northern Ireland in less visible ways. Cross-border commuting, once seamless, now faces occasional delays as goods vehicles undergo random checks. People living in border communities, such as Newry, Dundalk, or Derry–Londonderry, report a heightened sense of division. The removal of security infrastructure twenty years ago had been celebrated as a symbol of peace; the reintroduction of new port facilities and customs posts, even if only on the Irish Sea, has revived old sensitivities.

Youth and community organisations that rely on cross-border funding from the EU—such as the PEACE programme—faced uncertainty. The UK government has replaced EU structural funds with the UK Shared Prosperity Fund, but there are concerns about long-term continuity. The Good Friday Agreement's vision of a shared, reconciled society depends in part on social and economic cooperation across the island, which Brexit has complicated.

Possible Futures: Scenarios for Peace and Stability

The future of the Good Friday Agreement in a post-Brexit world depends on political will and institutional resilience. Several scenarios are possible.

Scenario 1: Stabilisation under the Windsor Framework

If the Windsor Framework works as intended, the Northern Ireland Executive will be restored and the Protocol's practical problems gradually resolved. Checks on goods from Great Britain will be minimal, and the Stormont Brake will give local politicians a mechanism to object to new EU rules that would have significant adverse effects. In this scenario, the Good Friday Agreement's institutions regain functionality, though the underlying constitutional tension remains. Peace would continue, but the relationship between Northern Ireland and the rest of the UK would be permanently altered.

Scenario 2: Gradual Erosion of the Agreement

If political stalemate continues, the institutions of the Good Friday Agreement may atrophy further. Without devolved government, decisions about Northern Ireland's affairs are taken by UK ministers, undermining local accountability and cross-community consent. This scenario risks creating a governance vacuum that could be filled by paramilitary groups or extremist voices. The open border would be preserved, but the spirit of partnership that sustains it would weaken.

Scenario 3: Constitutional Change

Brexit has accelerated debate about Irish reunification. Nationalists argue that Northern Ireland would be better off inside the EU, while unionists claim that Irish unity would bring economic disruption. The Good Friday Agreement provides a legal mechanism for a border poll, but the Secretary of State for Northern Ireland must call one if it appears likely that a majority would vote for unification. Current opinion polls show no majority for change, but demographics and shifting attitudes among younger voters could alter that balance. A border poll would be a polarising event that might test the peace process to its limits.

Scenario 4: A New Agreement

Some commentators argue that the Good Friday Agreement, while historic, may need updating to reflect post-Brexit realities. A new "UK–Ireland Accord" or revised Protocol could embed a sustainable relationship that recognises Northern Ireland's unique position. However, reopening the constitutional framework could risk unravelling the careful compromises that brought peace. For now, both the UK and Irish governments support the Good Friday Agreement as the bedrock of peace, even as they negotiate pragmatic adjustments.

Conclusion: The Enduring Relevance of the Good Friday Agreement

Brexit has tested the Good Friday Agreement in ways that its architects could not have anticipated. The open border, once taken for granted, is now a politically charged issue. The power-sharing institutions, once a model of conflict resolution, have struggled to function in the new environment. Yet the Agreement's core principles—consent, parity of esteem, and exclusive use of peaceful means—remain as relevant as ever.

The challenge for policymakers in London, Dublin, Brussels, and Belfast is to find a durable accommodation that respects the UK's sovereignty and the EU's integrity while preserving the protections that the Good Friday Agreement provides. The Northern Ireland Protocol and the Windsor Framework represent attempts to do so, but they are not final solutions. The peace process is not a fixed monument but a living set of relationships that require constant care and attention.

Ultimately, the Good Friday Agreement's greatest strength may be its flexibility. It was designed to accommodate different aspirations—British, Irish, and Northern Irish—and to allow for future change without resorting to violence. Brexit has proven that this flexibility can be strained, but also that the agreement's framework remains the only viable basis for a peaceful, democratic future in Northern Ireland. As historians and journalists continue to document this complex chapter, one fact stands clear: the peace built in 1998 is not guaranteed, but it must be defended by all who value stability over division.