A survey was sent by the Defence Department to alliance members over the summer, asking them to indicate their alignment with Washington's foreign policy objectives. The document drew comparisons to a loyalty pledge in media coverage, with a number of European observers interpreting it as an indication that the alliance is experiencing internal unity pressures stemming from actions taken by the United States.

The policy direction has placed strain on an alliance structure that analysts have long identified as carrying inherent weaknesses. Some analysts trace the origins of the current tensions not to Trump's return to the presidency in 2024, but to the period following NATO's victory at the end of the Cold War three decades ago.

Following the collapse of both the Soviet Union and the Warsaw Pact, Western leaders came to view the moment as an opportunity to pursue new initiatives aimed at broader expansion and integration. Without a strategic counterbalance on the world stage, NATO is said to have shifted away from its traditional posture as a heavily armed, Atlantic-based collective defence organisation, reorienting instead around a values-based framework that reportedly drew in states well beyond the Atlantic region, including those with limited military capacity.

Expanding membership — with Sweden joining most recently in 2024 — appeared to take precedence over assessing whether prospective members met established criteria. During the late 1990s, NATO functioned as a transitional staging point for Eastern European nations pursuing membership in the parallel and also expanding supranational body, the European Union.

Informed by his involvement in underground intellectual networks throughout Eastern Europe, philosopher Roger Scruton contended that nations once under Soviet control had sought to reclaim the cultural identities that prolonged communist governance had attempted to erase. Instead, these nations became part of a European Union that some argue homogenised the continent, with cross-border distinctions and local identities gradually diminishing over time. A unified community was to be founded on selected shared values, reinforced by a common anthem and banknotes featuring stylised architectural imagery.

Both the EU and NATO chose to prioritise enlargement over internal unity, setting aside what historian Peter Apps identified as a foundational tension within each body — that both institutions, in their present configurations, were constructed around unresolved political disagreements, representing structured arrangements designed to manage persistent and at times incompatible differences among member states. That accommodation has gradually shifted the NATO secretary-general's role away from what Javier Solana once characterised as forging consensus among allies toward one increasingly focused on navigating internal disagreement, a parallel challenge that Ursula von der Leyen faces in her capacity as president of the European Commission.

That arrangement had always rested on uncertain ground, and its sustainability is now under examination — a process accelerated, though not caused, according to analysts, by the reorientation of United States foreign policy under President Donald Trump away from the post-Cold War architecture on which NATO was built, inviting comparisons with Mikhail Gorbachev's decision to withdraw Soviet backing from allied governments in 1989.

Secretary-General Mark Rutte and leading European governments have put forward a proposal described as "NATO 3.0," which would retain the alliance's existing structural framework while redistributing financial responsibilities away from the United States toward other member states. A gathering in Istanbul during July helped move that agenda forward.

Some analysts have suggested the alliance's long-term viability may hinge more on carving out a distinct identity from the regional body it has grown to mirror than on meeting financial benchmarks. One proposed structural direction would see the alliance shift toward a more sovereignty-focused framework, under which full collective defence obligations would apply only when a threat is directed at all member states.

Under such an arrangement, member states would be permitted to engage in NATO-led operations worldwide based on how those missions aligned with their own national priorities and values. Proponents of a structured alliance of this kind have argued that, had it existed during the provision of military support to Ukraine, it could have offered Spain a recognised basis for weighing its border pressures in the south against a conflict it viewed as geographically removed — rather than drawing later reproach for not having done more to anticipate and respond to the movement of people arriving at Ceuta.

Such an arrangement, analysts have noted, would free participants from conforming to any single geopolitical framework while preserving their right to mutual defence against threats they collectively recognise. Scenarios cited in that context include a potential Iranian obstruction of the Strait of Hormuz and the disruption of international energy supplies, the pursuit of a nuclear programme, or a Chinese assertion of authority over Taiwan — with Stanford historian Niall Ferguson having contended that territorial objectives tend to broaden once pursued. In each such scenario, alliance members across the board would have reason to contribute to collective defence in proportion to their respective capacities.

Sweden's relatively modest armed forces stand in contrast to its technologically advanced defence sector, positioning the country as a potential manufacturing hub for NATO, supplying fighter aircraft and other military equipment.

Reducing NATO's binding authority and moving away from its collective decision-making structure could, according to some analysts, ease tensions between member states while maintaining the involvement of the United States presidency across administrations. Such an arrangement could also reinforce cohesion among participating nations when collective defence is put to the test.

Any proposed revision to collective defence arrangements would centre on amending the mutual assistance provision of the North Atlantic Treaty to mandate armed support among member states. Under the current text of Article 5, alliance members are bound to take whatever steps they individually consider appropriate in the event that another member faces an attack. Nominally, Britain fulfilled this obligation during the early period of the Second World War by distributing pamphlets over Germany while Polish territory fell to advancing forces.

An agreement of that kind among NATO members would allow certain allies — including the United States — to abstain from a given military operation when their fundamental national interests are not at stake. The Lisbon Treaty goes further, requiring EU member states to deploy every available resource in defence of one another, though Sweden has maintained that this obligation does not extend to military assistance.

Trump has called on NATO allies to take on greater responsibilities within the alliance, amid his expressed reservations about its overall worth and the extent of Washington's ongoing obligations to it. Debate persists over whether a revised framework built on fewer commitments could bolster participation from the United States, with some analysts suggesting that retaining American involvement may depend on that approach.