The immediate dispute is over basing and overflight, but the deeper argument is whether support for a U.S.-led war outside NATO command can be treated as an alliance expectation rather than a national decision.
France set the tone when Paris refused overflight for an Israeli aircraft carrying U.S. weapons into the conflict, a move that drew an angry response from President Donald Trump. French officials said the position had been consistent since the start of the war, according to Reuters’ report on France’s refusal and Trump’s backlash.
Italy then denied U.S. aircraft permission to use Sigonella air base in Sicily before heading to the Middle East, while Rome stressed that such requests are reviewed case by case under existing agreements and said there were no “critical issues or frictions” with Washington. That made Rome’s move notable even though Prime Minister Giorgia Meloni has otherwise avoided taking the hardest public line against the war, according to Reuters’ reporting on the Sigonella decision.
Spain took the hardest line. Madrid not only barred use of jointly operated bases but also closed its airspace to U.S. planes involved in the fighting. Defense Minister Margarita Robles called the war “profoundly illegal and profoundly unjust,” while Secretary of State Marco Rubio warned that a NATO setup under which the United States defends Europe but cannot secure wartime basing rights is “not a very good arrangement,” according to AP’s account of Spain’s airspace ban and the U.S. response.
That turned what began as a logistics fight into a direct argument about the alliance itself. U.S. Defense Secretary Pete Hegseth said “a lot has been laid bare” and left the fate of America’s commitment to NATO collective defense to Trump after allies put up “roadblocks or hesitations,” according to Reuters’ report on Hegseth’s NATO comments.
Why the Iran war is splitting NATO
This is the legal and political fault line beneath the current dispute: NATO’s core treaty obligation is collective defense after an attack on a member state, and the alliance’s own guidance says each ally provides the assistance it “deems necessary.” That does not automatically convert every U.S. request for overflight, basing or refueling into a NATO obligation, as explained in NATO’s official Article 5 explainer.
That distinction helps explain why Paris, Rome and Madrid can resist Washington without walking away from the alliance. The immediate break is political, strategic and psychological, not yet a formal treaty crisis. But once U.S. officials start tying access to bases and airspace to the future value of NATO, the argument stops being technical and becomes existential.
The Iran war also fits a longer pattern
This is not the first time European allies have tried to separate their own security interests from U.S. pressure around Iran or Iraq. In 2019, Reuters reported on a European maritime mission in the Strait of Hormuz that France, Italy and Spain backed specifically to avoid folding into a U.S.-led patrol.
After the U.S. killing of Iranian Gen. Qassem Soleimani in 2020, Reuters reported that NATO suspended its training mission in Iraq over regional security fears, another reminder that U.S. action against Iran can quickly spill into alliance business even when NATO is not directing the fight.
The older Iraq precedent is even more telling. A 2007 Reuters look back at the Iraq war divide noted that Italy and Spain had stood with Washington while France opposed the invasion, showing that the current alignment is new even if the underlying argument over American war aims, legality and allied consent is not.
For now, NATO remains intact on paper but visibly strained in practice. The bigger issue exposed by the Iran war is whether Washington can still assume that alliance solidarity extends beyond defending NATO territory and into U.S.-led wars that key European capitals neither planned nor endorsed.
