A great democracy builds an alliance based on combating a mutual enemy, securing trade lanes and safeguarding democracy. Each member of the alliance is an equal partner with an equal vote and all are expected to contribute militarily to the maintenance of the alliance.

Over time, the democracy becomes hegemonic and increasingly assertive over its alliance, demanding tribute and threatening to annex territory if it’s not forthcoming. It seizes the funds that were sent to maintain the alliance’s military and uses them for its own projects and policy.

When does the alliance cease and the Empire begin?

I’m referring to the Delian League. The alliance of Greek city-states created by ancient Athens to fight the Persians. Thanks to the above missteps, the league evolved into the Athenian Empire.

The story of its fall against Sparta in the Second Peloponnesian War, and how its mistreatment of allies contributed to that, is one of the great classical histories, as told by Thucydides, the father of ‘Realist’ international relations theory.

You’d be forgiven for thinking the first three paragraphs were in reference to the United States and the Trump administration’s relationship with her allies today. It is a cliché often repeated by historians that the only guide we have in predicting what may happen is found in what has happened. It’s so overused because it’s correct.

I’ll freely admit, the analogy doesn’t work under real scrutiny, but I hope I had you thinking! There are never going to be perfect analogies, times change and institutions, societies and technologies are wildly different. NATO and Europe are not the Delian League and the United States is not Athens. Europe’s institutions are far stronger and more important than anything the non-Athenian league had and there are far more internal checks to power in the United States than Athens. Aristophanes, however, would have found Washington an inexhaustible source of material.

Despite this, Europe and the United States do find themselves in a broadly similar position in the Trump administration. Trump has frequently threatened the annexation of Canada and Greenland, tariffed allies, undermined the Ukrainian war effort and brought into question the United States’ obligations under NATO’s Article 5.

Europe, until recently, had allowed its defence industries to shrink to a dangerous level so that when war returned to the continent in 2022, Europe was ill-prepared. Had the United States been under a Trump administration at the time, the situation in Ukraine may have been significantly worse for Europe as US military aid, vital at the time in Ukraine in a way it is much less so now, may not have flowed in.

Now we have a Europe that is steadily re-arming. Rheinmetall now manufactures more 155 mm artillery shells than the United States, Europe is developing its own Patriot missile equivalents and is working closely with Ukraine on developing the weapons that 21st century warfare requires.

Re-armament alone won’t help Europe secure the position it needs to. Europe needs to achieve three difficult goals to secure itself and, in many ways, the future of democracy. They are as follows: reform and build the institutions required to assert itself militarily, grow economically and remain politically unified, maintain the trans-Atlantic alliance, help turn the United States away from isolationism and actively sell the alliance system to ordinary Americans.

Europe’s institutions are strong. The European Union and NATO have achieved peace and cooperation between nations that had been warring for centuries. However, the EU as it is currently constructed does not allow for adaptability and agility in a way that the current security situation requires. The best example of this is Hungary, a state which until recently had blocked vital loans worth EUR 90 billion to Ukraine thanks to the pro-Russian stance of the former Prime Minister, Victor Orban. Because the union requires a unanimous vote on defence and industrial issues, Orban was able to unilaterally block EU foreign policy. If the EU is to be more assertive in its own defence, this has to go. Majority voting on defence, industrial and foreign policy measures is required. No single nation or wildly unpopular politician should be able to stymie the policy of a continent.

Secondly, Europe needs to develop an integrated defensive alliance capable of supplementing, rather than replacing, NATO. At its centre would be a European Armed Force, made up of troops assigned by each participating nation on a rolling basis and placed under the command of a centralised European Department of Defence.

Under this system, each participating state would assign a fixed proportion of its armed forces to the European force. These units would serve under a permanent European headquarters, train according to common doctrine, use interoperable equipment and deploy as part of multinational divisions. These would encourage further cooperation around defence procurement for national armies and would be able to slot into NATO deployments should the need arise.

While military investment can drive economic growth, Europe remains stuck struggling with low growth and productivity. Mario Draghi’s 2024 report The Future of European Competitiveness diagnoses the problems and proposes three key solutions: closing the innovation gap with the US and China, grabbing opportunities in green technology during the global decarbonisation process and securing key supply chains to avoid future vulnerabilities.

It’s a long and detailed plan, diving into nuance and detail that we don’t have the word count for here. Draghi considers that the bloc requires investments (public and private) of EUR 750–800 billion annually. Now, investment from SAFE and the relaxation of debt rules for arms expenditure in Resilience 2030 can go some way to achieving that, but thus far only 15.7% of the 383 recommendations have been fully completed with 41.3% part-way there according to the Draghi Observatory.

Europe won’t get there without political reform. Draghi highlights that Europe’s competitiveness gap is not entirely the result of weak competitiveness or insufficient investment but institutions that struggle to act collectively. As laid out above, one such way is to implement qualified majority voting and remove the unilateral veto, allowing core states to integrate faster and selling the EU as a geopolitical force to Europeans themselves, who receive waves of anti-EU messaging but very little that argues firmly and without reservation in its favour. All of this requires the political will, the effort and the grit to get it done. Europe has all it needs to compete as a superpower; it just needs to want it.

If Europeans do walk this path, we must maintain our ties with the United States. Calling for a clean break is understandable, after everything the current administration has done to Europe, but it is not in Europe’s interest to abandon the great swathes of Americans who feel a kinship with the continent, who share our values and our desire for a strong democratic alliance.

Our alliance systems are greater than the sum of their parts and against our rivals Europe and the United States should share burdens and goals. A renewed, geopolitically unified Europe would allow the US to pivot to Asia and balance against China while Europe deals with Russia. The UK and France can expand Europe’s nuclear umbrella. Five Eyes intelligence sharing can continue.

Trump’s administration will come to an end, when it does, Europe should be there to offer détente from a position of strength and work with the US as two equal partners, rather than a hegemon and 31 others. If we do not do this, then the EU will become perceived as (it already is in the current administration) an economic, social and political competitor against the United States. This will leave both powers distracted from their first-order adversaries (China for the US and Russia for Europe), working against one another and therefore significantly weakened in the face of these threats.

To achieve a real détente with the United States after Trump, Europe and the other middle powers need to reach Americans themselves. There are strong anti-European narratives, especially on the right of American politics, which have made bashing Europe politically attractive. This is embedded into the current administration, which has released a new initiative under the deceptively pleasant name Developing Civilizational Bonds, Democratic Resilience, and Rule of Law in Europe. Reading between the lines of this funding opportunity, it is designed to influence Europeans against the EU, erode European values and import the US right’s social, economic and political ideologies onto the continent.

The language is fairly clear: “For centuries, the transatlantic partnership has been rooted in a common understanding of natural law, virtue, and national sovereignty. However, European governments are increasingly drifting from these foundations through supranational bureaucratic overreach and partisan weaponization that concentrates power in technocratic institutions less accountable to democratic choices.”

It adds: “Supra-national institutions and governments are using state power to undermine fundamental principles of democratic self-government through overbroad and vague hate-speech laws and online content regulations that police and punish speech while suppressing political participation.”

Firstly, I have to question their assertion that the transatlantic partnership can be measured in centuries. However, let’s be clear, the supranational institution in question is the European Union itself. The goal behind this funding is to turn Europeans away from union, from the alliance that brought peace to a continent that has been in a state of near-constant warfare for centuries. As I stated earlier, the current administration sees Europe as a competitor. Not merely economically, but socially and politically. Americans question why they cannot have socialised healthcare and point to Europe, why maternity leave isn’t guaranteed and point to Europe, why the social safety net is so weak, and point to Europe. In answer to this, the administration has made it a goal to undermine the union and support parties and organisations that would turn Europe from what it could be: an assertive, strong geopolitical union that maintains its values and safety nets into a collection of squabbling states that mirror the US in their politics, their welfare policy and their economic inequality.

From the perspective of the current administration and its elite, billionaire backers, this is reasonable. In the same manner that a democratic Ukraine is a threat to the Russian system, a strong and independent Europe is a threat to the current administration’s worldview and long-term goals.

Europe cannot fight this conflict of influence and persuasion defensively. It must go on the offensive in the American heartland.

I do not propose that Europeans go to Minnesota and (filterless cigarette and espresso in hand) wax lyrical about the virtues of Europe. Europeans have an unfortunate snobbishness about Americans and American culture which is rightly perceived by our cousins across the pond. I propose that a fund mirroring and countering the State Department’s programme be set up. One that, instead of focusing on division, focuses on unity across the Atlantic, on our shared democratic values, on cultural exchange, language, accountability, equality and support for strong political checks and balances. Through grants to universities, journalists, veterans' organisations, think tanks, civic groups and cultural institutions, it should make the case against democratic decline and that a strong, united Europe is a future ally directly to the American people.

If the Trump administration believes it is legitimate to influence the political climate in Europe, we should be equally willing to influence the political climate in America.

The lessons from the failure of the Delian League are legion. Two vital ones here are that the moment one ally in an alliance manages to assert itself as a hegemon, you no longer have an alliance but an empire. Secondly, that no one member in an alliance should be allowed to become that hegemon.

Europe’s challenge is therefore twofold. It must become strong enough never again to depend upon the whims of a single American administration, and it must be wise enough not to break ties with our friends and instead build upon the relationships we already have with millions of Americans so that, when they are ready, the alliance can be renewed as a partnership of equals, not vassals.