How US disengagement from Europe forces old rivals to team up

In a historic move marking a shift in European defence strategy, French President Emmanuel Macron and Polish Prime Minister Donald Tusk are set to sign the Treaty of Nancy on Europe Day, symbolizing a new phase of Franco-Polish cooperation amid growing uncertainty over US security commitments.

The treaty, to be signed in Nancy—a city once governed by a dethroned Polish king—comes as Poland reevaluates its security alliances in response to Donald Trump's foreign policy signals suggesting a diminished American military presence in Europe and a softer stance toward Russia. Traditionally dependent on NATO and the US for its defence, an article by The Guardian concludes that Poland is now seeking to diversify its security guarantees by aligning more closely with France and exploring the potential for protection under France's nuclear umbrella. The agreement marks a dramatic reconciliation between France and Poland, whose relations within the EU had been strained for decades. France’s historical ambivalence toward EU's eastwards expansion and its past efforts to engage diplomatically with Russia, Poland's historic foe, were key points of contention.

Poland, on the other hand, has long favoured transatlantic defence ties and resisted EU-led defence initiatives. However, with geopolitical tensions rising—especially Russia's ongoing military operations in Ukraine—Poland is now proactively strengthening its ties with key European partners, including France, Germany, and the UK. According to the article, the Treaty of Nancy resembles the Franco-German treaty signed in 2019 and is intended to lay the groundwork for broader European defence collaboration. Although the treaty does not explicitly mention France’s nuclear arsenal, it emphasizes enhanced cooperation in several military areas, including air forces, missile defence, air-to-air refuelling, and artillery. 

Ongoing talks could also lead to Poland purchasing military and civilian aircraft from Airbus, and possibly submarines. Analysts argue that the treaty is a significant, though subtle, step toward offering eastern European nations like Poland a share of France’s nuclear deterrence—especially vital as Trump's unpredictability continues to shake European confidence in US defence guarantees. A Polish diplomat involved in the negotiations told the publication that the treaty's language on mutual defence closely mirrors the EU’s Lisbon Treaty, which obligates members to assist each other if attacked. While Poland had hoped for a direct mention of nuclear deterrence, its leadership prioritized securing broader security assurances before the upcoming presidential election on May 18. 

Tusk’s government views the treaty as essential given the current strategic volatility and US foreign policy drift. Importantly, Poland is not abandoning its pursuit of US nuclear protection. It continues to push for inclusion in NATO’s nuclear sharing arrangement, through which non-nuclear European nations store and are trained to deploy US nuclear weapons. Although countries like Germany, Belgium, and Italy already participate, Poland has faced resistance due to concerns that basing nuclear weapons near Russia’s border could escalate tensions. 

France has long maintained an independent nuclear policy and abstains from NATO’s nuclear planning group. But with Trump’s equivocal stance on defending NATO allies, the article points out that European countries are rethinking old assumptions and considering alternative security architectures. Germany’s newly elected chancellor, Friedrich Merz, has also expressed interest in deeper nuclear and defence collaboration with France, potentially revitalizing the Franco-German-Polish “Weimar Triangle” as a key pillar of Europe’s collective defence strategy, with the UK likely to play an auxiliary but vital role despite Brexit. 

By Nazrin Sadigova