Europe should prepare for a future in which it may have to work with, without or even against the United States, as the transatlantic relationship undergoes its most serious transformation since World War II, according to a major study from Germany’s SWP think tank.
The 81-page report, published by the German Institute for International and Security Affairs (SWP), argues that the Pax Americana that helped guarantee European security after World War II is coming to an end. Its central conclusion is that Europe can no longer assume the United States will remain a dependable security and political partner.
The report says this shift did not begin entirely with Donald Trump, but his second presidency has accelerated it dramatically. SWP argues that Europe now needs a long-term strategy to reduce its dependence on Washington, particularly in defence, technology, trade and international finance.
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Europe Faces a Five-to-10-Year Transition
According to SWP, becoming more independent from the US cannot happen quickly.
Europe would need a significant increase in resources over the next five to 10 years to strengthen its military capabilities, technological resilience and ability to make strategic decisions independently.
During that transition, Europe would remain vulnerable because it still depends heavily on the US, particularly for security and defence.
SWP therefore proposes a flexible strategy built around three options: working with Washington where cooperation remains necessary, acting without Washington where Europe has sufficient capacity, and potentially acting against Washington when European interests fundamentally conflict with US policy.
European Defence Is the Biggest Weakness
Defence is where Europe’s dependence on America is most significant.
For the foreseeable future, SWP expects NATO to remain central to European security. But it argues that Europe should accelerate the Europeanisation of NATO, building military capabilities that could function with much less American support.
That strategy should ultimately be compatible with a “Plan B” under which European countries either assume much greater control of NATO or establish a credible European defence structure outside the alliance if necessary.
The challenge extends beyond weapons.
The US continues to provide important intelligence, logistics and NATO command capabilities, while Europe has increasingly taken on more of the financial burden of supporting Ukraine.
Technology Could Become Another Pressure Point
Europe’s dependence on American technology represents another major vulnerability.
The report specifically examines what could happen if Washington used European reliance on US technology companies and infrastructure as leverage in political or economic negotiations.
SWP argues that Germany and the EU should build greater technological resilience and independent capabilities so that Washington cannot easily use those dependencies to extract concessions.
The same logic applies to international financial transactions and other strategically important infrastructure.
Reducing these dependencies would also strengthen Europe’s negotiating position even when relations with Washington remain cooperative.
Three Possible Futures for US-Europe Relations
SWP identifies three broad possibilities for the future of the transatlantic relationship: adaptation, transformation or breakdown.
Under adaptation, Europe would largely accept Washington’s demands because it remains too dependent on US security and technology to resist.
Transformation would preserve the relationship but fundamentally change it. Europe would assume greater responsibility for its own security while Washington steps back from its traditional leadership role.
The most extreme scenario is a breakdown, where disagreements over security, trade, technology, democratic values and international institutions become too significant to manage.
SWP does not argue that this outcome is inevitable. Instead, it says Europe should build enough independent capacity to ensure it has options under all three scenarios.
Europe May Need New Global Partners
The shift could also reshape Europe’s relationships beyond the US.
SWP examines how Europe could pursue policies toward Russia, Ukraine, China and the Middle East with less dependence on Washington.
It also argues that the EU should continue developing its soft power and seek new partnerships in areas including trade, climate policy, energy, development cooperation, international law and the United Nations.
The study sees particularly significant differences between Trump’s preference for unilateral action and rapid deal-making and the EU’s traditional emphasis on multilateral institutions, international law and longer-term cooperation.
The Transatlantic Relationship Is Not Necessarily Over
Despite its strong conclusions, the report does not recommend simply abandoning the United States.
The US and Europe remain deeply connected economically, militarily and technologically, and breaking those ties quickly would carry enormous costs.
Instead, SWP’s strategy is essentially one of risk reduction.
Europe should continue cooperating with Washington where that serves its interests, while simultaneously developing the military, technological, economic and diplomatic capabilities needed to operate independently.
Bottom line: SWP’s message is that Europe’s relationship with America is moving from dependence toward strategic flexibility. The EU may still need Washington for years, especially for defence, but it should prepare for a world in which American support can no longer be taken for granted. That means spending more on European defence, reducing technology dependencies and developing partnerships that give Europe greater freedom to act on its own.
Source: German Institute for International and Security Affairs (SWP), Research Paper 2026/RP 05
