In the Brexit Referendum held in June 2016, 52% of the voters in the United Kingdom voted in favor of leaving the European Union (EU). As a result of this referendum, the United Kingdom became the first country to decide to leave the EU after nearly half a century of membership. This decision was implemented with the official withdrawal process completed in January 2020. This unprecedented development in the history of the EU is discussed as being taken based on emotional and irrational motives rather than economic reasons. Indeed, although many economic analyses show that the United Kingdom gained significant benefits from EU membership, arguments focusing on migration and national sovereignty came to the forefront during the referendum campaign.
After Brexit, there were intense debates in European public opinion around the question of “can other countries also leave the EU?” For example, in countries such as France, Italy, and Poland, far-right populist circles developed discourses suggesting that the Brexit decision could create a domino effect. However, the Brexit case can be seen as an exception. Since the other members of the EU have completed their full integration with the Union, the cost of a possible separation attempt will be extremely high, and the repetition of a similar process will be almost impossible.
The EU membership of the United Kingdom had a limited integration from the beginning. The United Kingdom government did not take part in the Eurozone (common currency), which is one of the main projects of European integration, and in the Schengen Area, and obtained special exemptions (opt-out) in some policy areas such as justice and home affairs.[1] This exceptional position was a factor that made the United Kingdom’s withdrawal from the Union relatively more possible institutionally and technically. On the other hand, when looking at the members outside the United Kingdom, the centralization and integration process of the EU has accelerated since the 1990s.
After the 1992 Maastricht Treaty and the 2009 Lisbon Treaty, the Union structure gained a more centralized character, and the “transfer of competences” of member states to common institutions and policies increased. Although the Brexit decision emerged during this integration period (as a reflection of the rising populist wave in Europe in the 2010s), the withdrawal of the United Kingdom did not trigger similar initiatives in other countries. Debates such as “Frexit” in France, “Italexit” in Italy, and “Polexit” in Poland came to the agenda after Brexit, while in the same period the majority of EU members further deepened their Eurozone and Schengen integrations. Since the 2010s, many member states have adopted the common currency, and the Schengen Area has expanded, enlarging the area within Europe where border controls were lifted. Therefore, today the idea of leaving the EU has become a much more costly and distant possibility for many member states compared to the past.
When the nature of the Brexit decision is examined, it is seen that this process was based on the emotional and political reactions of voters rather than economic realities. Independent economic reports prepared before the referendum in the United Kingdom revealed that EU membership provided net benefits to the country.[2] However, a significant part of the public acted with concerns about migration, identity, and sovereignty, ignoring these warnings. Due to the political debates on Turkey’s accession to the EU, the refugee burden, and the functionality of the EU, a referendum was held. During the referendum campaign, anti-EU populist politicians such as Nigel Farage influenced the voters through slogans such as “taking back control of the country” and stopping the influx of foreign migration.[3] As a result, the choice of Brexit manifested itself as a collective emotional reaction caused by populist politicians among a part of the public rather than a rational calculation despite economic risks.
There are various structural factors that make it difficult for EU members to pursue a path of separation similar to Brexit. First of all, the exit of Eurozone member states from the common currency would require putting their national currency into circulation again. Such a step would create the possibility of great uncertainty and turmoil in the financial system of the country concerned. Similarly, leaving the Schengen free movement area would mean re-establishing border controls that had been abolished in the European continent for decades. This situation would have extremely destructive consequences in socio-economic terms. In addition, for Central and Eastern European members in particular, the financial aid and funds provided by the EU are indispensable. Countries such as Poland, Hungary, and Romania, which obtain the highest net benefits from the EU budget, would lose the financial resources they benefit from in many areas, from infrastructure investments to agricultural subsidies, if they left the Union.[4] This would create a major gap in the economies of the countries concerned and make it difficult for them to achieve their development goals. In short, breaking away from the EU would mean concrete and heavy financial losses for these countries beyond being merely a political decision.
Indeed, even the example of the United Kingdom reveals the difficulty of leaving the EU. Although the London administration was able to implement the decision to leave with the flexibility provided by remaining outside full integration, the Brexit process caused serious problems both within the United Kingdom and across Europe. One of the most complex aspects of Brexit was the Northern Ireland issue. In order to preserve peace on the island of Ireland, a special arrangement (Northern Ireland Protocol) had to be made between the United Kingdom and the EU, which caused debates about the territorial integrity and sovereignty of the United Kingdom.[5] In addition, the withdrawal of the United Kingdom from the EU single market created new customs barriers and border controls in trade transactions, leading to disruptions in supply chains. As a result, many international companies shifted their operations from Britain to Eurozone countries. The decline in foreign direct investment and the shaking of London’s position as a global financial center were also among the economic consequences observed after Brexit.
The EU has achieved an unprecedented level of success in economic integration. This economic integration, achieved through the single market, common currency, and financial regulations, has bound member states together with strong ties. Therefore, if a new separation possibility from the EU is to be the case today, it is more likely to stem from political and socio-cultural motives as in the United Kingdom rather than economic ones. Because for member states, the cost of breaking away from economic integration is almost unbearable. However, if political integration, namely further unity in decision-making processes; the alignment of common foreign and security policies; and the strengthening of democratic legitimacy cannot be achieved, the possibility that national governments feel excluded within the Union or that anti-EU discourses rise under populist pressures increases.
In this context, the priority of the EU may be to focus on completing political integration alongside economic integration and to create a European identity. The withdrawal of the United Kingdom also stemmed from reluctance towards political and cultural integration rather than economic reasons. The withdrawal of countries with full integration from the Union would be a destructive scenario in terms of political stability and international effectiveness as well. Therefore, the EU may focus both on increasing political solidarity among its current members and on strengthening the institutional adaptation of new members.
As a result, Brexit is largely a consequence of irrational motives and the limited integration of the United Kingdom within the EU. As former French President de Gaulle foresaw, the United Kingdom never fully integrated into the EU and ultimately withdrew. The future of Europe lies not in separations but in deepening internal integration in economic and political dimensions as well as resolutely continuing enlargement with new members. As a Union that has completed economic integration, the EU may henceforth move towards political integration and the creation of a European identity. This goal may both prevent new separations and enable the Union to continue to exist as a more effective, coherent, and strong actor at the global level.
[1] “Brexit the Ultimate Opt-out: Learning the Lessons on Differentiated Integration”, European Papers. New Options for Differentiated Integration in the European Union, vol. 7, no. 3 (2022): pp. 1211–1227, Maria Kendrick, doi: 10.15166/2499-8249/608, (Accessed: 28.08.2025).
[2] “Five Years On: The Economic Impact of Brexit”, National Institute of Economic and Social Research (NIESR) blog, Dr Benjamin Caswell ve Hailey Low, 31 January 2025, https://niesr.ac.uk/blog/five-years-economic-impact-brexit, (Accessed : 28.08.2025).
[3] “It’s the slogan, stupid: The Brexit Referendum”, University of Birmingham (Perspectives), Dr Tim Haughton
https://www.birmingham.ac.uk/research/perspective/eu-ref-haughton, (Accessed : 28.08.2025).
[4] “Freezing EU funds: An effective tool to enforce the rule of law?”, Centre for European Reform (CER) Insight, Zselyke Csaky, 27 February 2025, https://www.cer.eu/insights/freezing-eu-funds-effective-tool-enforce-rule-of-law, (Accessed : 28.08.2025).
[5] “Protocol on Ireland/Northern Ireland (Revised Protocol to the Withdrawal Agreement)”, UK Government, October 2019 (PDF), https://assets.publishing.service.gov.uk/media/5da863ab40f0b659847e0184/Revised_Protocol_to_the_Withdrawal_Agreement.pdf, (Accessed : 28.08.2025).
