President Trump launched his attack on Iran on February 28, 2026, with very short advance-notice to NATO allies, and virtually no consultation or effort to bring the alliance together for joint action.

Yet, despite this, Trump has severely criticized several European nations for refusing to bases within their countries or areas of control.  In particular, Trump has been vociferous in his criticism of British Prime Minister, Keir Starmer for his initial refusal to allow US bombers to utilize the air base on Diego Garcia, and Spain’s president, Pedro Sánchez, for his refusal to allow use of the joint base in Andalusia. 

In response, Trump said about Starmer: “This is not Winston Churchill that we’re dealing with.” Trump has threatened to cut off all trade with Spain as punishment

Starmer has since relented on U.S. use of Diego Garcia for “defensive” purposes.  But is announcement of deployment of British ships to the theatre of war was met with disdain from Trump, who said they were no longer needed.  Trump exclaimed, “We don’t need people that join Wars after we’ve already won.”

Sánchez also has continued to be in the crosshairs of Trump’s ire.  He already had refused to increase Spain’s defense spending to 5% of GDP as Trump had demanded. He has described the strikes on Iran as a "disaster" and an "unjustified military intervention." Trump has called Sanchez a “terrible leader,” and Spain a “terrible ally.”

French President Emmanuel Macron has backed Spain, and declared that Trump’s attack on Iran was “outside the framework on international law.”

By contrast, Germany has received praise from Trump for Chancellor Friedrich Merz’s decision to allow Ramsted Airforce Base to be used for operations related to Iran. Italy’s Prime Minister Giorgia Meloni was praised by Trump as a “great leader” after she allowed use of Italy’s bases.

Poland and the Baltic states have been mostly supportive of the war with Iran.  This is not surprising given their vulnerability to Russian aggression in light of the fact that the Iranians have been helping Russia by supplying drones to be used against Ukraine. 

E.U. Commission president Ursula von der Leyen’s comments have mostly focused on the effect that the war will have on European energy, and she has repeatedly expressed support for the Iranian and Lebanese people.  She also has made reference to a new European Security Strategy, to project power, increase European influence, and “protect our territory, economy, democracy and way of life.”

Kaja Kallas, the E.U.’s High Representative for Foreign Affairs and Security Policy, has warned of chaos and instability stemming from the Iran war.  However, she also has called the Irania regime an “exporter of war,” and recently has announced sanctions against a number of Iranian officials and entities.

The manner in which Trump has initiated and conducted the war in Iran without involvement from European allies likely has done further harm to the unity of the alliance, especially after the hard feelings left by the threats to take over Greenland. The reluctance of certain allies to allow American use of bases, while understandable given the lack of notice or consultation, also will not be helpful.

However, the long-term effect of the Iran war on NATO will likely depend on how the war proceeds.  If the U.S. gets bogged down, Trump may be forced into a position of making amends with certain allies and turning to NATO for help. 

For example, opening the Strait of Hormuz is of critical importance to both the U.S. and Europe.  Yet, despite the impressive U.S. naval armada assembled in the region, opening the Strait to commercial traffic has proved to be a vexing problem for Trump.  This has been exasperated by the fact that the U.S. retired its few mine sweeping vessels in September of 2025.  But Belgium, the Netherlands, the UK, and France all have mine sweeping capabilities that could be used in the effort.

If the Europeans prove themselves to be helpful, or even invaluable, in the conflict (by providing mine sweepers or otherwise), Trump perhaps will be forced to recognize the value of NATO, which could result in a renewed U.S. commitment to the alliance.

On the other hand, if the U.S. claims a quick and decisive victory without substantial help from NATO allies, this could further harden Trump’s view that the U.S. gets nothing from the alliance and that “NATO is nothing without us.”  Such a view could lead to continuation of the U.S. path toward less involvement in, or even withdrawal from, NATO.

In either event, it is likely that the Europeans will continue policies toward strengthening their own defense without reliance on the U.S.