The Strategic Case for Starmer: Why Britain Must Rejoin Europe

Britain at the strategic crossroads: the Union Jack piece returning to the European board under the stars of the EU.

From antiquity to the modern age, the great texts of strategy insist on one lesson above all: politics is not about short-term manoeuvre but about aligning means and ends to create enduring power. Sun Tzu argued in The Art of War that the supreme skill is to win without fighting, by seizing the ground on which victory becomes inevitable.¹ Clausewitz taught that wars are decided by striking at the enemy’s “centre of gravity” — the source of strength that holds an adversary together.² Machiavelli insisted that fortune rewards audacity when the tides of history shift.³ Thucydides chronicled how city-states thrived or perished on their ability to forge coalitions and anticipate threats.⁴ And Lawrence Freedman, in his modern classic Strategy: A History, distilled these lessons into the maxim that strategy is “the art of creating power.”⁵

For Keir Starmer and Labour, the defining strategic opportunity of the coming years is not merely to manage Britain’s decline outside Europe, but to reverse it — by advancing the case for rejoining the European Union. This is not nostalgia for 2016, but the strategic reorientation that aligns Britain’s domestic needs, party-political advantage, and geopolitical responsibilities. To borrow Clausewitz’s phrase, Europe has become the “centre of gravity” in Britain’s political struggle, and only by returning to it can Labour secure lasting dominance at home and restore Britain’s role abroad.

Public Opinion and the Economic Ground

The public has shifted decisively. YouGov’s long-running tracker shows that 54–56 per cent of Britons now support rejoining the EU, compared to around 30 per cent opposed.⁶ Even among Leave voters, regret is common, with majorities describing Brexit as a failure.⁷ This is not an abstract trend: the economic costs are tangible. The Office for Budget Responsibility estimates that Brexit will reduce UK GDP by around 4 per cent in the long run, primarily due to reduced trade intensity.⁸

Business investment, goods exports, and labour mobility have all suffered. What Sun Tzu called “the ground” has changed. What once looked like hostile terrain for Labour — risking the wrath of Leave constituencies — has become favourable terrain, provided the issue is framed as a matter of growth and security rather than culture war.

Two further facts strengthen the case. First, European public opinion is receptive: polling in 2025 showed majorities in France, Germany, Italy, and Spain supporting the UK’s return.⁹ Second, while incremental resets (like the Windsor Framework) provide modest relief, they are widely acknowledged as insufficient.¹⁰ The strategic dividend lies in full reintegration. For Labour, the message is simple: Rejoin to grow; rejoin to lead.

Party-Political Strategy: Outflanking Farage and Dividing the Right

Rejoining is not only an economic imperative; it is a political weapon. Nigel Farage thrives on declinism, offering only the hollow promise that Britain could prosper alone if only “the establishment” tried harder. His Reform UK has surged in polling, at times leading both Labour and the Conservatives. For instance, YouGov in August 2025 recorded Reform at 28 per cent, Labour at 21, Conservatives at 17, and the Liberal Democrats at 16.¹¹ Yet under first-past-the-post, raw vote shares mean little without distribution and coordination. The 2024 election proved this: Labour and the Lib Dems together secured 46 per cent of the vote, compared with 38 per cent for the Conservatives and Reform combined, and yet won an overwhelming seat majority.¹² Geography and tactical voting — Duverger’s Law in action — matter more than aggregates.

This is why a Labour–Liberal Democrat pact or merger around rejoining the EU is strategically potent. It fuses adjacent constituencies — social democrats and liberals — around a median-voter project of growth and internationalism. By contrast, a Conservative–Reform rapprochement fuses culturally distant blocs — traditional moderates and anti-system radicals — and risks bleeding support to the centre. Indeed, Lord Ashcroft’s 2025 polling found that 26 per cent of Conservative and Reform voters would be less likely to support a joint ticket, undermining the very logic of alliance.¹³ In game-theoretic terms, Labour–Lib Dem is the minimum-winning coalition, while Con–Reform is an over-aggregation that maximises defections.¹⁴

Here Machiavelli’s lesson applies: fortuna favours boldness. By seizing the initiative, Starmer can lock in a progressive hegemony, marginalise Corbyn’s breakaway project, and paint Farage as the author of decline — or worse, as a “Putin puppet” whose crowning political achievement, Brexit, was celebrated most loudly in Moscow.¹⁵

The Referendum Gambit

Labour’s parliamentary dominance creates a once-in-a-generation opportunity to structure the battlefield. Starmer could legislate for a referendum offering a binary choice: rejoin the EU or maintain the status quo. Excluding a “no deal” option would fracture the Leave coalition, forcing voters to defend an unpopular arrangement or embrace renewal. Critics would decry a stitch-up; strategists would call it Clausewitzian — striking at the enemy’s centre of gravity by denying them favourable terrain.

Such a referendum would be fought not on abstractions but on trust and betrayal. The 2016 Leave campaigns promised prosperity, sovereignty, and stronger services; Britain instead received stagnation, division, and diminished global clout. Public cynicism is profound, but it is now directed at Brexit’s architects. Labour can harness this by reframing Brexit as the great betrayal of the British people. In contrast, rejoining can be presented as the optimistic choice: restoring growth, regaining influence, and securing Europe against the twin uncertainties of Trump’s America and Putin’s aggression.

Geopolitical Realities: Strength in Union

Here Thucydides’ warning resonates: “the strong do what they can and the weak suffer what they must.”¹⁶ A Britain outside Europe is reduced to rule-taking, pleading for carve-outs, and watching from the sidelines. Inside the EU, Britain regains its status as a coalition-builder in the world’s largest market and a partner in shaping sanctions, energy security, and technological standards.

The Russia Report by the Intelligence and Security Committee in 2020 documented how Moscow exploited Western divisions to weaken democratic institutions.¹⁷ Brexit was a strategic gift to Putin, fracturing Europe at a critical moment. Rejoining the EU would be the opposite: a strategic setback for Moscow, a reassertion of unity, and a signal that Britain has relearnt the oldest truth of strategy — that strength comes through coalition. At a time when Trump’s America may retreat from European commitments, Britain’s leadership inside Europe would be a counterweight of immense value.

Conclusion: Creating Power

Sun Tzu would advise securing the position before the battle is joined; Clausewitz would counsel targeting the true centre of gravity; Machiavelli would urge audacity when the current changes; Thucydides would remind us that strength lies in alliances. Freedman would simply say that strategy is the art of creating power.

For Keir Starmer, rejoining the European Union is the strategy that creates power. It creates economic power by restoring Britain’s growth potential. It creates political power by uniting Labour and the Liberal Democrats, dividing the right, and marginalising both Farage and Corbyn. And it creates geopolitical power by anchoring Britain where it belongs: in the European camp that stands against authoritarianism.

The opportunity is here. The public has shifted, the evidence is overwhelming, and the threats are mounting. If Starmer seizes this moment, he will not merely manage Britain’s decline; he will shape its destiny.

References

1. Sun Tzu, The Art of War, trans. Lionel Giles (1910), ch. 3.

2. Carl von Clausewitz, On War, ed. Howard & Paret (Princeton University Press, 1976), Book 6, ch. 27.

3. Niccolò Machiavelli, The Prince (1513), ch. 25.

4. Thucydides, History of the Peloponnesian War, Book V, “The Melian Dialogue.”

5. Lawrence Freedman, Strategy: A History (Oxford University Press, 2013), p. xii.

6. YouGov, “Tracker: Should the UK rejoin the EU?” (2025).

7. Ipsos, “Brexit: Majority say leaving EU more of a failure than success” (2024).

8. Office for Budget Responsibility, Economic and Fiscal Outlook (Nov 2022).

9. YouGov Eurotrack Poll, July 2025: majorities in France, Germany, Italy, Spain support UK return.

10. Institute for Government, UK–EU Relations After Brexit (2024).

11. YouGov voting intention, 10–11 August 2025.

12. House of Commons Library, “General Election 2024: results and analysis” (2024).

13. Lord Ashcroft Polls, “Conservative and Reform Voters: Prospects of an Alliance” (Feb 2025).

14. William Riker, The Theory of Political Coalitions (Yale University Press, 1962).

15. ISC, Russia Report (2020).

16. Thucydides, History of the Peloponnesian War, Book V.

17. ISC, Russia Report (2020).