The escalating confrontation with Iran is putting one of NATO’s core principles to the test: inter-alliance solidarity. While US President Donald Trump is leading a hardline approach, in cooperation with Israel, to curb Iran’s nuclear progress, key European countries are adopting a cautious, restrained, and critical stance.
This gap is not merely tactical, it undermines the foundations of the alliance. When Europe tells Trump, “this is not our war,” despite its commitment to assist the US, it underscores a broader strategic rift. The comparison is stark: had President Franklin D. Roosevelt responded similarly to Europe’s calls during World War II, the continent’s fate could have been drastically different. Today, Hitler’s successors would be ruling all of Europe.
A strategic divide: regional defense vs. global confrontation
Founded in 1949 after World War II, NATO was designed as a collective defense alliance to protect Western Europe and anchor US involvement against the Soviet threat. Its guiding principle, Article 5, states that an attack on one member is an attack on all.
Today, however, the Trump administration is seeking to expand NATO’s role beyond defense, urging proactive engagement against global threats, chief among them Iran. Europe, by contrast, maintains that not every conflict outside the continent warrants NATO intervention, advocating de-escalation and the preservation of diplomatic channels.
The result is a widening conceptual divide between Washington and European capitals.
Frustration in Washington is particularly directed at countries such as the UK, France, Italy, and Spain, which are seen as not carrying their fair share of the burden. This perception is eroding trust and cohesion within NATO, shifting it from a values-based alliance to a more conditional partnership.
Trump has made his position clear: “Those who do not participate cannot expect full protection.” He has also stressed that “the Iranian threat is not only American, it is Western,” while arguing that Europe is not contributing enough.
He has called for active European participation, not just rhetorical support, and criticized reliance on diplomatic condemnations. As part of this push, he has proposed raising defense spending to 5% of GDP and hinted that US protection may not be guaranteed for countries that fall short.
Between economic pressure and European autonomy
Trump has linked security commitments to economic relations, arguing that the US is “losing twice,” both by funding security and by running trade deficits. His broader message signals a shift from multilateralism to a transactional approach: those who do not contribute may not receive full protection.
While the US is unlikely to fully withdraw its commitments, signs point to increasing pressure on Europe in the short term. Over the longer term, this dynamic could accelerate Europe’s pursuit of “strategic autonomy,” including stronger internal defense cooperation.
NATO: crisis or transformation?
NATO is not on the verge of immediate collapse, but it is facing a profound identity crisis. The growing gap between US demands for a more active, combat-ready alliance and Europe’s preference for a cautious, measured approach could lead to significant structural changes.
At its core, Trump is seeking to transform NATO into a more engaged alliance beyond Europe, with broader burden-sharing. Europe, meanwhile, appears to be moving toward greater defense independence.
If this divide persists, NATO is unlikely to disband, but it may be reshaped in fundamental ways.