The Iran war , as anticipated, featured prominently at the NATO leaders’ summit in Ankara on 7–8 July, which was officially centred on Ukraine and defence spending.
Its political fallout marked a turbulent start to the two-day gathering, highlighting differing threat perceptions among allies and reviving debate over NATO’s ability to maintain cohesion as it faces widening security challenges beyond its eastern flank.
US President Donald Trump’s tensions with European governments and his Iran policy loomed over the conference, as he reiterated criticism of NATO allies' defence spending, and once again rebuked European members for not backing the US-Israeli war with Iran.
Defence investments worth billions pledged by NATO leaders did little to appease the US president, who was still angered by some European allies' refusal to back the military campaign that he launched alongside Israel without consulting them.
Trump singled out Britain, Italy, Germany, and France for failing to do more to help US forces during the conflict, overlooking NATO’s position that such involvement was beyond its remit. He also raised the prospect of cutting off all trade with Spain for Madrid’s refusal to spend more on defence and back the US war on Iran.
While accusing European member states of insufficient loyalty, Washington’s military campaign against Iran relied significantly on their support earlier this year. Unlike Spain, which denied the use of its bases for US operations, the UK and other European allies enabled the Iran campaign through logistics or access to existing military facilities.
NATO Secretary-General Mark Rutte said around 5,000 US military flights operated from European bases during the Iran conflict, describing Europe as "one big platform of power projection" for the United States.
“It was a political show: Trump seeking revenge against leaders he believed didn’t show enough loyalty,” Daniel Hamilton, a non-resident senior fellow at the Brookings Institution who focuses on transatlantic and international affairs, told The New Arab .
He stressed that, despite Trump’s accusations, NATO’s European allies provided varying levels of logistical assistance and access, but most were reluctant to join an offensive war, amid unease over Israel's push for military action. A position that did not align with the broader political and military support the US leader had hoped to garner from allies.
Speaking to The New Arab , Jamie Shea, an associate fellow with the International Security Programme at Chatham House, said the American president had diverted attention from the NATO event’s intended success despite European allies’ efforts on burden-sharing.
"The problem with Trump is that he always sees the glass as half empty,” the former senior NATO official commented, “he’s not ready to put past frustrations behind him”.
Briefly comparing the Iran conflict with the 2003 Iraq war, Iulia Joja, a senior fellow at the Middle East Institute (MEI) focusing on European security, told The New Arab that the split in European countries' positions has shifted from intra-European to transatlantic. While the US-led Iraq invasion divided European allies, most have today chosen to stay out of another war in the Middle East.
“Politically, we will continue to see this disparity across the Atlantic over threat perceptions and military action in the Middle East,” MEI’s scholar said.
She observed that last week’s summit lacked discussion on how NATO allies could address issues such as navigation in the Strait of Hormuz , de-mining, or easing the blockade, adding that the transatlantic divide has made European allies reluctant to raise them.
“Europeans have a very different threat perception. Iran is not currently viewed as a major direct military concern, and that is reflected in NATO’s posture on the southern flank,” Joja said, remarking that the political repercussions of the war have so far remained contained, affecting Gulf and Arab nations - which Iran blamed for hosting US military bases - rather than American allies in Europe.
The Iran war exposed a broader dilemma within NATO as European governments sought to avoid endorsing an offensive campaign beyond the alliance’s defensive mandate, while maintaining strategic ties with the United States and preserving transatlantic cohesion.
Disagreements over how to handle the war risk further straining relations among allies, with both sides of the conflict remaining at an impasse and growing concerns that fresh hostilities could unravel the fragile ceasefire reached in mid-June.
Transatlantic tensions at the Ankara summit were further tested by renewed confrontation between Washington and Tehran, with the two sides exchanging strikes as leaders of the alliance gathered for the event.
Following new US attacks on more than 80 Iranian targets, Iran launched missiles and drones at US-linked military sites in Bahrain and Kuwait, with the Revolutionary Guards (IRGC) claiming it struck 85 sites.
The flare-up prompted Mark Rutte to defend the US attacks, while European governments tried to balance pressure from the Trump administration with efforts to prevent divisions over the conflict.
But even as the Iran conflict threatened to derail the meeting’s agenda, European NATO allies worked to display a picture of unity through higher defence spending and military readiness, while the NATO head helped keep Trump engaged with an alliance that continues to underpin European security.
“The summit, under the current circumstances, could have gone a lot worse. NATO members secured a declaration, reaffirmed their ties, and struck defence deals,” Olga Oliker, director for European Security at the International Crisis Group (ICG), told The New Arab .
She also suggested that, especially under the Trump administration, some in the US have seen NATO as an alliance meant to simply follow Washington’s lead, a view that European member states have pushed back against to varying degrees.
Yet, even in the face of increasing tensions with Washington and diverging views over how to respond to Middle East crises, the ICG’s analyst pointed out that none of the ongoing discussions undermines NATO’s cohesion.
The majority of allies still see Russia’s war against Ukraine and threats along NATO’s eastern flank and the Baltic region as the alliance’s primary security challenge.
For Shea, NATO has proved resilient through past crises, especially those that fall outside its founding purpose of defending allied territory.
The Ankara summit declaration reinforced the alliance’s collective defence pledge under Article 5, vowed at least $50 billion in new defence contracts and $70 billion for Ukraine in 2026, recognised Europe's expanding share of NATO’s defence burden, and maintained that Iran "must never have a nuclear weapon" while urging Tehran “to fully respect freedom of navigation in the Strait of Hormuz”.
Brookings’ Hamilton drew a clear distinction between NATO as an institution and the strategic differences of individual member states, with some countries aligning with Washington and others taking a different approach. “Allies will continue to have different security priorities, including over the Middle East, but NATO itself remains focused on its core mission,” he said.
The transatlantic affairs specialist noted that the alliance is moving toward the so-called “NATO 3.0” vision, where Europe assumes greater responsibility for its own defence and the US remains a key strategic ally, however less central as Europe’s security guarantor. A transformation he anticipated “will take years”.
Europeans are expected to effectively fill the gap left by US forces and capabilities as they depart, and take on primary responsibility for Europe's conventional defence against Russia and other threats.
Although the Ankara conference reaffirmed NATO’s commitment to unity, it stopped short of setting out a roadmap for how Europe should take on a larger share of the defence burden in practice. It also remains unclear what shape NATO will take in the future.
While transatlantic tensions did not result in a rupture at the annual meeting, the Iran war has shown that crises outside NATO’s territory can still become security concerns for the alliance.
“Many issues beyond NATO’s borders can ripple back into the alliance,” said Hamilton, hinting at the Middle East, migration, terrorism, and instability in Africa.
A prolonged US involvement in the Iran conflict could strain NATO indirectly by diverting American weapons and resources needed elsewhere.
Shea admitted that an extended Middle East crisis could lead to a “diversion of resources” away from the alliance’s support for Ukraine. He pointed to US strikes against Tehran consuming munitions like short- and long-range missiles and Patriot air defence systems, which could create a difficult “military balancing act” for allies struggling to preserve stocks needed for Kyiv’s defence.
“Donald Trump is caught between seeking to end the war and the need to show strength against Iran over the Strait of Hormuz,” the NATO expert added, noting that the president is stuck in a strategic dilemma: he wants to restore the status quo in the Strait of Hormuz, while the IRGC is aiming to emerge from the war with control over it.
The protracted conflict has also raised concerns over Washington’s reliability . Even though NATO’s foundation remains stable, mounting unpredictability from Washington has prompted allies to reconsider their reliance on the US.
Shea warned of a growing divide between Washington and European allies over the threats shaping Europe’s security, alluding to the gradual US political and military disengagement from Europe as the allies’ primary concern.
For Oliker, the more instability spreads outside Europe’s borders, especially in the Middle East, the harder it becomes for NATO members to persuade others that European security is a global concern.
Although Iran is not a NATO responsibility, there is uncertainty over how far resumed fighting could escalate or whether it might spread to other countries.
“Obviously, Iran is outside NATO territory,” NATO chief Rutte said at last week’s conference. “That doesn’t mean NATO could never get involved.”
Alessandra Bajec is a freelance journalist currently based in Tunis
Follow her on Twitter: @AlessandraBajec
Edited by Charlie Hoyle