Ten years after the Brexit referendum: Britain and the EU in a world of disorder

Six weeks before the Brexit referendum, I shared a platform with David Cameron, the then prime minister, and I argued that Brexit was a massive geopolitical mistake. The case for Britain to remain in the EU was “about power and influence, and the interests and values they project, in a world that is changing fast”. The speeches were overshadowed, to put it mildly, by an overnight briefing from Downing Street that a vote to leave was a “vote for World War 3”. That claim was counter-productive because it was absurd – but the core argument about the consequences of separating Britain from continental politics is even more true today than it was ten years ago.  

At just the wrong time, Brexit weakened Britain, weakened Europe and weakened the West. It weakened Britain because we lost an economic and political force multiplier. It weakened Europe because the UK had been a positive economic and political presence in the EU. And it weakened the West because it created division within Europe just as President Trump was about to introduce division across the Atlantic. 

It would be wrong to trace a direct line from the Brexit vote to Russia’s invasion of Ukraine. But it would be right to say that the invasion of Ukraine has exposed the central folly of Brexit’s logic – above all, the assumption that it was possible, even necessary, for Britain to be national or global in its outlook, but not regional. Today, EU unity, strength and finance in support of Ukraine are central to Britain’s number-one foreign policy priority – yet our contribution to, and influence over, a shared European effort must come from outside the room where the decisions are made. 

This matters because we face a geopolitical scene marked by a modern version of the ‘Kindleberger Trap’: the fading of a once-dominant global superpower’s influence, creating a power vacuum and stoking instability. In such a world, global public goods – open markets, territorial integrity and climate security – are up for grabs. From the invasion of Ukraine to the US war in Iran, from China’s assault on the international trading system to the neglect of the global commons such as pandemic preparedness, the scramble for insulation from disorder is accelerating. 

“The question is not whether to turn the clock back, but what future relationship to build instead.” 

Mark Carney, speaking in Davos in January 2026, called this a moment of “rupture” – and he was right. But we should also follow his maxim of waking up every morning and thinking “what can I do?” rather than “what has President Trump tweeted?”. For Britain, outside the EU but indispensable to European security, the answer has to begin by acknowledging how the world has changed in the last decade. 

The right lens to see today’s world is as ‘multi-aligned’, with fluid and transactional coalitions working together on different issues. This is, I think, a better description than the idea of ‘multipolarity’, which implies too great a degree of stability. There are many players in this new global situation, often with asymmetric power, as Iran has demonstrated at the Strait of Hormuz. The idea of a balanced, ‘multipolar’ order seems to me to be fanciful. In today’s world we do not have a multipolar equilibrium; what we have instead is a multi-aligned search for buoys in a choppy sea. 

Global hyper-connectedness means that new cross-border risks have emerged, so the need for co-operation between countries is greater than ever. Such co-operative efforts represent countervailing power against the marauding forces of disorder – not just against the 60 or so wars going on at the moment, but also against power plays on every continent. 

In facing the new global context, Europe faces internal as well as external demons. The defeat of prime minister Viktor Orbán by the Hungarian people removes one obstacle to EU decision-making in the short term, but the appeal of nationalism and resentment over internationalism and co-operation remains potent. French voters, heading into the presidential election of 2027, hold more than their own country’s fate in their hands. But Britain cannot afford to wait for the French results before acting. 

Europe’s biggest security priority today is containing Russia at a time when Washington, in effect, gives it a free pass. The US National Security Strategy under President Trump makes that clear. A central question, therefore, is how to accommodate Ukraine within EU institutional structures – which British governments of both parties have, ironically, supported. That requires institutional flexibility of a kind the EU has rarely shown: it might mean tiers of membership, or ‘associate membership’. We, in the UK, need to take off our blinkers, clarify our own interests, and engage urgently with these live debates taking place in European capitals. 

I have no doubt that Britain’s security and prosperity depend on a much stronger, institutional relationship with the EU. But a ‘reversal’ of Brexit is literally impossible – not just because the deal that we had before 2016 is not on the table now, but also because the EU itself is changing. The question is not whether to turn the clock back, but what future relationship to build instead. 

It is vital to combine the strengths of the EU and its member-states, the UK and other European countries outside it, such as Norway. We cannot contain Russia without the EU. We cannot renew our economy by pretending the EU does not exist. We cannot secure our energy future without EU engagement. But all of this requires imagination about a structured institutional relationship that goes well beyond anything currently on offer. We need to recognise that this is a new debate – not a replay of an old one.

David Miliband is president and CEO of the International Rescue Committee, former UK foreign secretary (2007-10) and a member of the CER’s advisory board. 

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