Ben Tonra

The challenges posed by Brexit to Irish foreign, security and defence policy are multiple and cross-cutting. The first and most obvious impact is a reinforced Europeanisation of Irish diplomacy. The 2018 establishment of the ‘New Hanseatic League’ or ‘Hansa’ comprising the three Baltic States, Denmark, Finland, Ireland, the Netherlands and Sweden is part of this, as has been a visible strengthening of bilateral ties with both Paris and Berlin. While the Hansa initiative is not much more than an informal ginger group of like-minded states which share perspectives on economic governance and some institutional issues, it has also been mooted as a wider diplomatic lever on EU foreign policy. The launch of the Global Island project – aimed at a 50 percent expansion of Ireland’s global footprint over the next six years (and encompassing a major expansion in the Irish diplomatic network) should also be seen in this context. This initiative underlines an ambition to “ensure that Ireland is better positioned to build the alliances necessary to advance its interests and defend its positions in a post-Brexit EU, while also helping to secure our deep and positive relationship with the UK and its constituent parts into the future.” The latter part of that statement is key.

The absence of the UK from EU councils creates a massive deficit in bilateral relations between Ireland and the UK. The easy daily interaction of ministers, diplomats and officials of the two governments and their associated administrations is now lost. So too, over time, will be the close personal relationships developed through those interactions. For both governments – but most especially for Ireland – there is an urgent need to strengthen bilateral institutions and to think about new means to ensure that the two governments can engage with one another effectively. The recent strains on the bilateral relationship caused by the fraught negotiation of the Article 50 Withdrawal Agreement underscore this need – as does the pressing requirement to re-establish functioning government in Northern Ireland. While the Good Friday/Belfast Agreement offers an institutional framework for North-South and East-West relations, it was created within the context of shared EU membership. This now needs serious re-evaluation if not re-engineering in a post-Brexit context – perhaps including the use of an analogue to the Franco-German structure of regular bilateral summits and joint cabinet meetings.

Irish diplomacy within the EU may also soon face its own challenges regarding EU solidarity. The stalwart EU26 support on the Irish border issue, will not face anything like an invoice for payment. However, there is no doubt that claims on solidarity can’t be seen as unidirectional. Ireland’s exposure on corporation tax and the associated issues of a ‘digital tax’ and the consolidated corporate tax base is uncomfortable and feeds into the creation of the aforementioned Hansa group where Irish policy can be most comfortably be situated. A deepening of EU economic governance may also pose challenges as Ireland defines itself as a fiscally conservative northern European state. Defence is another critical area where this arises.

Recent far-ranging development of new policies and structures in EU defence cooperation have been facilitated by the absence of UK vetoes. The initiation of Permanent Structured Cooperation in defence (PESCO), the proposed €40+ billion European Defence Fund and reinforced budgetary and defence policy coordination have been developed – in an EU context – at near break-neck speed over the last two years. While the EU’s combined military capacity has fallen by upwards of 20 percent as a result of Brexit, its collective political will has – at least at the rhetorical level – risen substantially. Ireland’s traditional safe haven in the context of such proposals – nestled in the crux of Anglo-French disagreement – has disappeared and thus opened a horizon of more difficult policy choices. In addition, while Irish-UK defence cooperation, enumerated in a 2015 bilateral memorandum, is formally unaffected by Brexit, Ireland may yet be anxious to facilitate the broadest possible UK engagement with CSDP.     

In sum, Brexit marks a watershed moment for Irish foreign, security and defence policy. The loss of the UK as an EU partner can only be partially mitigated, while Ireland establishes for itself a new and deeper centre of gravity in Europe and at the same time seeks to extend and widen the web of its global relationships.


Professor Ben Tonra is Full Professor of International Relations at the University College Dublin School of Politics and International Relations. Heteaches, researches and publishes in European foreign, security and defence policy, Irish foreign, security and defence policy and International Relations theory.


This article is part of an ongoing blog series ‘Brexit Countdown’ by the Political Studies Association (PSA) and Political Studies Association of Ireland (PSAI).  


To read the entire series, please see below:

  1. An introduction to the Brexit Countdown Blog Series by Feargal Cochrane and Muiris MacCarthaigh
  2. What’s the likely impact of Brexit on Higher Education in Northern Ireland? by Cathy Gormley-Heenan
  3. Brexit and a second Scottish Independence Referendum: What happens next? by Margaret Arnott
  4. What's the difference? British and Irish attitudes towards the EU by Kathryn Simpson
  5. Brexit and devolution in Wales by Roger Awan-Scully
  6. The Backstop: a ‘flexible and imaginative’ solution? by David Phinnemore
  7. Culture, the arts and Brexit by Kate Mattocks
  8. Brexit and implications for Scottish Devolution by Nicola McEwen
  9. Is Brexit propelling Northern Ireland towards Irish unity? by Katy Hayward
  10. Blair and Brexit by John O'Brennan
  11. The looming possibility of a retaliatory relationship between the UK and the EU by Will Phelan
  12. Brexit: Ethnopolitical dimension by Timofey Agarin
  13. Irish-British relations: Preparing for momentous change by Paul Gillespie
  14. Brexit, gender and Northern Ireland: Changing the state-society relationship by Yvonne Galligan
  15. Beyond the backstop: the DUP’s role in Brexit by Jon Tonge
  16. Brexit, political parties & power-sharing in Northern Ireland by Sophie Whiting
  17. Brexit and devolution in England: What's at stake by Arianna Giovannini
  18. Brexit, diplomacy and defense by Ben Tonra
  19. Empathy, minorities and Brexit by Richard English
  20. Young people and Brexit: Not all that we think by Emily Rainsford
  21. Is the Backstop a Red Line Too Far? by Etain Tannam
  22. The UK's view of the EU by Simon Usherwood
  23. The invidious impact of Brexit on Ireland's policy landscapes by Mary C. Murphy
  24. Looking into the abyss: A European perspective by Brigid Laffan
  25. Britain after Brexit by Anand Menon
  26. Brexit as Political Irony by Feargal Cochrane
  27. The Brexit Countdown Series: Some concluding thoughts, and an appeal by Muiris MacCarthaigh and Feargal Cochrane