How might the escalation of the US‑Iran conflict reshape NATO’s collective defense doctrine and influence future burden‑sharing negotiations among member states?
The US-Iran conflict that erupted on February 28, 2026, with Operation Epic Fury represents the most significant test of NATO's collective defense architecture since the alliance's founding in 1949How US/Israeli Iran Strikes Will Penalize Global Prospectsantiwar +1. While NATO Secretary General Mark Rutte has explicitly stated that the alliance is "not itself involved" in the military operations, the conflict has exposed fundamental tensions in how collective defense obligations apply to out-of-area contingencies and has intensified pressure on burden-sharing arrangements at a moment when Europeans face a 2027 deadline to assume primary responsibility for their own conventional defenseNATO's Rutte praises US, Israeli military action against Iran but says alliance won't be involved | Reutersreuters +1.
The US-Israeli joint military campaign launched at 1:15 a.m. ET on February 28, 2026, constituted the largest coordinated air operation in Israeli Air Force history, involving over 200 fighter jets attacking 500 targets and striking more than 1,000 targets within the first 24 hoursHow US/Israeli Iran Strikes Will Penalize Global Prospectsantiwar +1. The operation achieved a strategic objective unprecedented in the region's modern history: the killing of Supreme Leader Ali Khamenei, confirmed by Iranian state media on March 1, 2026, prompting 40 days of national mourningUS-Israel strikes on Iran: February/March 2026 - House of Commons Libraryparliament +1.
Iran's retaliation has been far more extensive than previous incidents of conflict escalation. Unlike the limited response following the 2020 killing of IRGC-Qods leader Qasem Soleimani—which targeted only one US military base in Iraq—or the June 2025 strikes that prompted only an attack on a US base in Qatar, the current Iranian counter-strikes have targeted an unprecedented range of locations across seven countries: Israel, Bahrain, Kuwait, Qatar, the United Arab Emirates, Oman, and JordanUS-Israel strikes on Iran: February/March 2026 - House of Commons Libraryparliament +1. The number of missile, drone, and other attacks is estimated in the several hundredsUS-Israel strikes on Iran: February/March 2026 - House of Commons Libraryparliament .
Critically for NATO's collective defense calculations, Iranian attacks have directly struck facilities housing allied forces. UK bases in Bahrain came under attack, with approximately 300 British military personnel positioned within several hundred yards of missile strikes'No Military Resources': NATO Split Over Iran War? After UK, This Nation Vetoes Joining Conflictyoutube . The British Royal Air Force base at Akrotiri in Cyprus—an EU and NATO-proximate territory—was hit by an Iranian-made Shahed drone that struck the runway, while two ballistic missiles were fired in the direction of the Mediterranean islandBritish Base Hit in Cyprus, Drones Downed as Iran War Widens | TIMEtime +1. A French naval base hangar in the UAE was also struckNATO BASES UNDER FIRE? Iran Hits UK and French Facilities, Russia, China, and North Korea Back Iranyoutube . As of 57 hours into the operation, four US service members had been killed and four others remained seriously woundedTop U.S. general outlines initial timeline of U.S. military operation in Iran | Reutersreuters .
NATO's official stance represents a carefully calibrated posture of strategic support without institutional engagement. Secretary General Rutte has stated unequivocally that "there are absolutely no plans whatever for NATO to get dragged into this or being part of it, other than individual allies doing what they can to enable what the Americans are doing together with Israel"NATO's Rutte praises US, Israeli military action against Iran but says alliance won't be involved | Reutersreuters . Simultaneously, Rutte praised the US-Israeli operation as "really important" because it is "taking out, degrading the capacity of Iran to get its hands on nuclear capability, the ballistic missile capability"NATO's Rutte praises US, Israeli military action against Iran but says alliance won't be involved | Reutersreuters .
This posture reflects the structural constraints embedded in NATO's founding treaty. Article 5 of the Washington Treaty is geographically limited by Article 6 to attacks against the territories of member states and forces and ships at sea north of the Tropic of Cancer or in the MediterraneanNATO's Article 5: The Conditions for a Military and a Political Coalitioncolumbia . The wording was deliberately designed in 1949, at US Senator Arthur Vandenberg's insistence, to prevent the United States from defending allies' colonial possessions in Africa, Asia, and Latin AmericaNATO's Article 5: The Conditions for a Military and a Political Coalitioncolumbia . While the treaty is silent on where a military response can take place—allowing the post-9/11 Afghanistan campaign despite the attack occurring on US soil—the geographic trigger for collective defense remains constrainedNATO's Article 5: The Conditions for a Military and a Political Coalitioncolumbia .
Article 5 invocation requires unanimous consensus among NATO allies and has been triggered only once in the alliance's 75-year history—following the September 11, 2001 terrorist attacksNATO’s Article 5 Explained: How Collective Defense Works and When It’s Triggered | The Belfer Center for Science and International Affairsbelfercenter +1. Even when invoked, each ally retains complete discretion to take "such action as it deems necessary," which could include non-military responsesNATO's Article 5: The Conditions for a Military and a Political Coalitioncolumbia +1. This flexibility—designed to preserve national sovereignty and constitutional processes—means Article 5 does not automatically commit any member to military actionNATO's Article 5: The Conditions for a Military and a Political Coalitioncolumbia .
Despite Iranian attacks on UK bases in Bahrain and Cyprus, and the strikes on French facilities in the UAE, there has been no formal Article 5 deliberation within the North Atlantic Council. The attacks on Cyprus—while triggering defensive responses from Greece, Germany, and France, which sent naval frigates and F-16 fighter jets—have not prompted collective defense invocationTehran vows to strike European countries if they join Iran war | Euronewseuronews . Italy summoned the Iranian ambassador to protest the Cyprus strike, demonstrating diplomatic solidarity without escalating to alliance-level responseItaly summons Iran envoy over Cyprus strike - Al Arabiyaalarabiya .
However, NATO has demonstrably increased its operational posture. The alliance's AWACS radar aircraft based in Turkey have shifted their surveillance focus from Russia to Iran as tensions mountedNATO Increases Iran Surveillance Flights as US Considers Military Options - Bloombergbloomberg . NATO's missile defense system—originally developed with the Iranian ballistic missile threat in mind and including the US Aegis Ashore site in Romania and US Navy destroyers out of Rota, Spain—is on heightened alertNATO keeps watchful eye on Iran’s response to ‘existential’ war | Stars and Stripesstripes . A senior NATO military official confirmed a round-the-clock vigilance posture covering "land, air, sea, cyber and space domains"NATO keeps watchful eye on Iran’s response to ‘existential’ war | Stars and Stripesstripes .
The Iran conflict has exposed significant divisions among European NATO members regarding the appropriate level of participation in US-led Middle East operations—divisions that carry profound implications for future burden-sharing negotiations.
The United Kingdom has adopted the most active posture among European allies while carefully circumscribing its role. Prime Minister Keir Starmer explicitly stated that "the United Kingdom was not involved in the strikes on Iran" and that "we are not joining these strikes"US-Israel strikes on Iran: February/March 2026 - House of Commons Libraryparliament +1. However, following Iranian attacks that struck airports and hotels where British citizens were staying and the Bahrain base that "narrowly missed British personnel," Starmer accepted a US request to use British bases "for that specific and limited defensive purpose"US-Israel strikes on Iran: February/March 2026 - House of Commons Libraryparliament +1.
The UK's legal rationale invokes Article 51 of the UN Charter—collective self-defense—rather than NATO's Article 5, with the government publishing a summary of its legal advice'No Military Resources': NATO Split Over Iran War? After UK, This Nation Vetoes Joining Conflictyoutube . British jets are flying defensive operations and have "already successfully intercepted Iranian strikes"'No Military Resources': NATO Split Over Iran War? After UK, This Nation Vetoes Joining Conflictyoutube . The UK Ministry of Defence confirmed a joint operation with Qatar that successfully destroyed an Iranian drone heading toward Qatari territoryBritish Base Hit in Cyprus, Drones Downed as Iran War Widens | TIMEtime .
Germany has refused military participation entirely. Foreign Minister Annalena Baerbock stated that Berlin "does not have the corresponding military resources" and "the government has no intention of participating in any way"'No Military Resources': NATO Split Over Iran War? After UK, This Nation Vetoes Joining Conflictyoutube . Chancellor Friedrich Merz warned that the US-Israeli strikes risk creating "another Iraq-style quagmire" but deliberately avoided "lecturing" Washington, stating that "legal assessments under international law will achieve relatively little" and "now is not the moment to lecture our partners and allies"How every EU country responded to the strikes on Iran – POLITICOpolitico +1.
Merz's position reflects the German calculation that maintaining US support for Ukraine—and avoiding Trump administration retaliation—outweighs concerns about international law compliance. Germany has pledged soldiers would remain "ready for defensive measures should they be attacked" but nothing beyondWhy Europe's leaders have struggled to speak as one on Iranbbc .
France, together with Germany and the UK, issued an E3 statement confirming no involvement in the initial strikes while expressing willingness "to assist in some capacity with the U.S. and Israeli action against the regime, potentially through enabling necessary and proportionate defensive action to destroy Iran's capability to fire missiles and drones at their source"How every EU country responded to the strikes on Iran – POLITICOpolitico . Following the strike on a French naval base hangar in the UAE, Paris reinforced its defensive posture and deployed frigates to support Cyprus's defenseNATO BASES UNDER FIRE? Iran Hits UK and French Facilities, Russia, China, and North Korea Back Iranyoutube +1.
Prime Minister Pedro Sánchez was the only EU leader to openly condemn the US-Israeli attack. "We reject the unilateral military action by the United States and Israel," Sánchez declared, characterizing the strikes as "an escalation" that "contributes to a more uncertain and hostile international order"How every EU country responded to the strikes on Iran – POLITICOpolitico +1. Spain also refused to allow US use of its bases for operations—a decision that Trump explicitly condemned, threatening to "cut off all trade with Spain"WATCH: Trump Blasts Spain’s Refusal on US Iran Bases, Warns UK and Allies ‘No One Can Stop Us | AC15youtube .
Turkish President Recep Tayyip Erdoğan drew "a firm line" stating "no Turkish boots on Iranian soil" and warning that "any military strike on Iran would ignite chaos across the region"NATO Nation 'ENTERS' Iran-US Conflict, Reveals 'CALL DETAILS' With Trump; 'DO NOT ATTACK...'youtube . Erdoğan revealed direct talks with both Iran's president and Trump, seeking to mediate tensionsNATO Nation 'ENTERS' Iran-US Conflict, Reveals 'CALL DETAILS' With Trump; 'DO NOT ATTACK...'youtube .
The Iran conflict unfolds against the backdrop of the most significant restructuring of transatlantic burden-sharing since NATO's founding. At the June 2025 Hague Summit, allies committed to investing 5% of GDP annually on defense by 2035—a "quantum leap" from the previous 2% target established at the 2014 Wales SummitDefence expenditures and NATO’s 5% commitment | NATO Topicnato +1. This commitment comprises two categories: at least 3.5% of GDP for core defense requirements (troops, weapons, capabilities) and up to 1.5% for defense-related spending including critical infrastructure protection, cybersecurity, civil preparedness, and defense industrial base strengtheningDefence expenditures and NATO’s 5% commitment | NATO Topicnato +1.
More immediately, the Pentagon has established a 2027 deadline for European allies to take over "the bulk of defense responsibilities on the Continent"US sets deadline for Europe to lead NATO by 2027, report says | Stars and Stripesstripes . US officials told European counterparts in Washington that if allies miss this deadline, "the U.S. could stop participating in some NATO activities"US sets deadline for Europe to lead NATO by 2027, report says | Stars and Stripesstripes . The Trump administration's 2025 National Security Strategy explicitly articulates this shift: "The days of the United States propping up the entire world order like Atlas are over. We count among our many allies and partners dozens of wealthy, sophisticated nations that must assume primary responsibility for their regions"[PDF] National Security Strategy | The White Housewhitehouse .
The scale of the European capability gap is sobering. A Bruegel analysis found that if NATO had to defend against Russia without US support, European allies would need at minimum 50 new combat brigades and approximately 300,000 troops, including 1,400 tanks, 2,000 infantry fighting vehicles, and 700 artillery systems—"more combat power than currently exists in the French, German, Italian and British land forces combined"US sets deadline for Europe to lead NATO by 2027, report says | Stars and Stripesstripes . The estimated annual cost would exceed $250 billion, or roughly 3.5% of European GDPUS sets deadline for Europe to lead NATO by 2027, report says | Stars and Stripesstripes .
Several European officials characterized the 2027 deadline as "unrealistic," noting that "Europe needs more than just funding and political will to replace certain U.S. capabilities—particularly unique intelligence and space surveillance assets that cannot be procured elsewhere except through the Pentagon"ðºð¸ U.S. May Partially Exit NATO by... - Ukraine Breaking News | Facebookfacebook .
The Iran conflict has intensified existing fissures in burden-sharing consensus, most visibly through Spain's formal exemption from the 5% GDP target. Prime Minister Sánchez secured a unique modification to the Hague Summit communiqué: while "allies commit" to the target, Spain was recognized as having "a different path," capping its commitment at 2.1% of GDPWhy Spain is not meeting NATO spending targets - Atlantic Councilatlanticcouncil +1. Spain's 2024 defense budget stood at just 1.28% of GDP—NATO's lowest relative to its economyNATO leaders are set to agree on a historic defense spending pledge, but the hike won't apply to all | The Associated Pressap .
From a legal standpoint, Spain has not violated any treaty obligation. The North Atlantic Treaty does not require members to commit a fixed percentage of GDP to defense; Article 3 mandates only that parties "maintain and develop their individual and collective capacity to resist armed attack" while leaving implementation to national discretionNetherlands dispatch: Spain rejects NATO’s 5% defense spending guideline, reaffirming legal sovereignty and exposing cracks in alliance cohesion - JURIST - Newsjurist . The spending targets have always been political benchmarks rather than binding legal obligationsNetherlands dispatch: Spain rejects NATO’s 5% defense spending guideline, reaffirming legal sovereignty and exposing cracks in alliance cohesion - JURIST - Newsjurist .
However, the practical consequences are substantial. Trump's response to Spain's position—threatening to "cut off all trade" and singling out Spain as the "only country that in NATO would not agree to go up to 5%"—demonstrates the political costs of defectionWATCH: Trump Blasts Spain’s Refusal on US Iran Bases, Warns UK and Allies ‘No One Can Stop Us | AC15youtube +1. Spain's additional refusal to allow US use of its bases during the Iran conflict compounded tensionsWATCH: Trump Blasts Spain’s Refusal on US Iran Bases, Warns UK and Allies ‘No One Can Stop Us | AC15youtube . The Trump-Sánchez confrontation reached a crescendo at the January 2026 Davos summit, where Trump described the Sánchez administration as a "free rider" and suggested potential expulsion if Spain fails to meet spending mandatesThe NATO schism: Madrid’s strategic divorce and the 5% collisionynetnews .
NATO risks evolving into a "tiered alliance," where states like Poland, the US, and the Baltic nations shoulder the rising burden of deterrence while others leverage opt-outs to prioritize domestic spendingNetherlands dispatch: Spain rejects NATO’s 5% defense spending guideline, reaffirming legal sovereignty and exposing cracks in alliance cohesion - JURIST - Newsjurist . This divergence may erode the mutual risk-sharing that underpins Article 5's credibilityNetherlands dispatch: Spain rejects NATO’s 5% defense spending guideline, reaffirming legal sovereignty and exposing cracks in alliance cohesion - JURIST - Newsjurist .
The Iran conflict introduces a dimension that could fundamentally alter NATO's collective defense calculations: the demonstrated capability and stated intent of Iran to strike European territory. Secretary General Rutte explicitly acknowledged that Iran's "growing nuclear and ballistic missile capabilities pose a threat not only to the region but also to Europe"NATO not involved in US-Israeli war on Iran: Rutte - TRT Worldtrtworld +2. He characterized Iran as "an existential threat" to Israel and "a huge threat to us here in Europe"Tehran vows to strike European countries if they join Iran war | Euronewseuronews .
Iranian ballistic missile capabilities can reach European NATO territory. The Shahab-3 missile has a range of 1,300 kilometers, operational missiles reach 1,500-2,500 kilometers, and the Khorramshahr can strike up to 3,000 kilometers—sufficient to target Romania, Hungary, and GreeceMap reveals how Iran's missiles can hit Europe after Tehran secretly ...the-sun +1. According to an Iranian Parliament member of the Commission on National Security and Foreign Policy, "all of Europe, and in particular Britain, France and Germany are in range of Iranian MRBMs"Ballistic missile program of Iran - Wikipediawikipedia . Shahed suicide drones have a range of up to 2,000 kilometers, meaning they could also strike parts of EuropeMap reveals how Iran's missiles can hit Europe after Tehran secretly ...the-sun .
Tehran has made this threat explicit. The Iranian foreign ministry spokesperson declared on March 3, 2026, that any European military action would be "an act of war" and would "expand the country's retaliatory strikes to target European cities and countries"Tehran vows to strike European countries if they join Iran war | Euronewseuronews . The spokesperson stated that "defensive is synonymous to offensive" and warned that European countries taking sides with aggressors "have already done enough against Iran"Tehran vows to strike European countries if they join Iran war | Euronewseuronews .
This threat calculus intersects with NATO's existing missile defense architecture. The European Phased Adaptive Approach (EPAA), introduced in 2009 as a response to Iran's ballistic missile production capability, has deployed advanced interceptors in Romania and planned additional deployments to defend against Iranian strikes on European populations, forces, and critical infrastructureWhat Will an Iran Deal Mean for NATO-Russia Relations?youtube +1. The alliance's February 2025 Integrated Air and Missile Defence Policy explicitly identifies NATO as "closely monitoring all state or non-state actors with air and missile capabilities, capable of reaching the Euro-Atlantic area," including IranNATO Integrated Air and Missile Defence Policy | NATO Official textnato .
The Iran conflict accelerates a long-standing debate about NATO's geographic scope. The alliance has been grappling with "outside of area" operations since at least the Kosovo conflict in 1999, which the Washington Summit's revised Strategic Concept addressed only indirectlyNATO's Article 5: The Conditions for a Military and a Political Coalitioncolumbia . The September 11 attacks—which triggered Article 5 invocation for operations in Afghanistan, 7,000 miles from where the US was attacked—demonstrated that while the treaty specifies where an attack must occur to trigger collective defense, it is "silent about where a military or other response can take place"NATO's Article 5: The Conditions for a Military and a Political Coalitioncolumbia .
The 2022 Strategic Concept, adopted in the wake of Russia's invasion of Ukraine, brought NATO "into a new era of great power competition" while identifying "conflict, fragility, and instability" in the Middle East, North Africa, and the Sahel as security challenges affecting the allianceFull article: Reinforcing deterrence: assessing NATO’s 2022 Strategic Concepttandfonline +1. A SAIS analysis noted that "the region is facing more of the presence of emerging major powers—particularly Russia and China—while witnessing a smaller footprint from the United States," compelling NATO to be "more active in the region before the US completes its pivot away, particularly in terms of Iran's nuclear and ballistic missile programs"NATO 2030: Towards a New Strategic Concept and Beyondjhu .
NATO's regional engagement frameworks remain the primary institutional mechanism for Middle East cooperation. The Istanbul Cooperation Initiative (ICI), launched in 2004, includes four Gulf Cooperation Council states—Bahrain, Kuwait, Qatar, and the UAE—with Oman and Saudi Arabia participating in selected activitiesIstanbul Cooperation Initiative | NATO Topicnato . The NATO-ICI Regional Centre in Kuwait, established in 2017, recorded its "highest level of activity" in 2025, implementing 25 qualitative activities covering maritime security, cybersecurity, CBRN security, emergency planning, and critical infrastructure protection HE GCCSG: The GCC-NATO Partnership is an Advanced Model for Enhancing Regional and International Security gcc-sg . Its 2026 action plan includes 31 diverse activities HE GCCSG: The GCC-NATO Partnership is an Advanced Model for Enhancing Regional and International Security gcc-sg .
The GCC's activation of its Joint Defence Agreement—declaring that an attack on one member will be considered an attack on all—parallels NATO's Article 5 and creates potential for more formal burden-sharing arrangements between the two alliance frameworksWhat GCC’s activation of NATO-style joint defence pact means for regional security - TRT Worldtrtworld . Gulf states demonstrated "active military support for US-Israeli operations despite traditional diplomatic relationships with Iran," with Qatar's participation in air defense operations representing "particularly significant strategic realignment"US Military Operation Against Iran: Market Impactdiscoveryalert . Trump administration officials have framed this as a "shared responsibility and burden-sharing arrangement among allies"US Military Operation Against Iran: Market Impactdiscoveryalert .
The Iran conflict unfolds amid the most intensive European effort to reduce strategic dependence on the United States since NATO's founding. According to ECFR's public opinion polling, "fewer Europeans than ever consider the United States under President Donald Trump 'an ally that shares our interests and values'"Suspicious minds: Why Europeans are considering their post-America nuclear options – European Council on Foreign Relationsecfr . More than 70% of citizens in Germany, the UK, and France viewed America in mid-2025 as an unreliable security guarantor—a sharp decline from 2024, when over 55% considered the US reliable or somewhat reliableFunctional Adaptation Without Much Love: NATO and the Strains of EU–US Relations - ECPSpopulismstudies . In April 2025, 81% of EU citizens supported a common defense and security policy among member states—the highest level since 2004Functional Adaptation Without Much Love: NATO and the Strains of EU–US Relations - ECPSpopulismstudies .
President Macron's announcement on March 2, 2026—coinciding with the Iran conflict—that France would expand its nuclear arsenal and could deploy nuclear-armed aircraft to allied countries for the first time represents a potential "major shift for Europe's defense"NATO 'welcomes' Macron's nuclear warhead drive - Europe - CGTNcgtn . Eight European countries, including Britain, Germany, Poland, and Sweden, agreed to participate in what Macron called a "forward" nuclear deterrence schemeNATO 'welcomes' Macron's nuclear warhead drive - Europe - CGTNcgtn . NATO welcomed "the opportunity to expand consultation on nuclear issues with France in order to ensure a coherent, coordinated approach"NATO 'welcomes' Macron's nuclear warhead drive - Europe - CGTNcgtn .
This nuclear initiative follows the July 2025 UK-France "Northwood Declaration," which stipulated the "European dimension" of deterrence and provided a "blueprint for credible European deterrence"Northwood Declaration: The Future of European Deterrence?csis . As Washington explicitly calls for Europe to assume more defense responsibility, "Northwood and Lancaster House 2.0 offer a blueprint for credible European deterrence, not only between France and the United Kingdom but with other European partners as well"Northwood Declaration: The Future of European Deterrence?csis .
However, European defense autonomy confronts structural constraints. Despite calls for strategic independence, European NATO states derived 64% of their arms imports from the United States in 2020-2024, up substantially from 52% in 2015-2019Global arms transfers report shows US allies are main bearers of Washington's strategic costs: expertsglobalsecurity . As Secretary General Rutte observed, anyone who believes Europe can defend itself without the US should "keep on dreaming"Europe begins its slow retreat from US dependence - POLITICOpolitico . The €150 billion EU defense investment program finalized in May 2025 restricts non-EU and non-partner-country components to 35% by cost—effectively limiting US participation—but cannot quickly replicate unique American capabilities in intelligence, space surveillance, and missile defenseEurope begins its slow retreat from US dependence - POLITICOpolitico .
The Iran conflict introduces an energy security dimension with direct implications for how NATO's new 1.5% GDP infrastructure and resilience spending is defined. European natural gas prices have nearly doubled following Qatar's halt of liquefied natural gas production after facility attacksWar-Induced Inflation Spike Looms Over Europe’s Economic Recovery - The New York Timesnytimes . The EU imports a majority of its oil and gas, making it vulnerable to global price volatility, and Qatar produces approximately a fifth of the world's LNG supplyWar-Induced Inflation Spike Looms Over Europe’s Economic Recovery - The New York Timesnytimes .
Iran's signaled willingness to interfere with maritime traffic through the Strait of Hormuz—which handles a massive share of global oil transport—has disrupted shipping activity, caused insurance premiums to surge, and created immediate uncertainty for energy tradersIran War Shock: Markets Panic as Oil Routes Face Disruptionyoutube . War risk insurance premiums have surged to approximately 1% of hull and machinery value across Middle East Gulf operationsUS Military Operation Against Iran: Market Impactdiscoveryalert .
The Hague Summit communiqué's language on the 1.5% category—protection of critical infrastructure, network defense, civil preparedness, resilience, innovation, and defense industrial base strengthening—provides broad scope but limited definitional clarityThe Hague Summit Declaration | NATO Official textnato . The Atlantic Council has called for NATO to "establish a list of agreed critical infrastructures, starting with those most relevant to military operations," including airports, rail, seaports, roads, electric grids, pipelines, and hospitals, as well as determining whether private-sector spending should count toward the targetNATO needs to define the substance of its 1.5 percent pledge - Atlantic Councilatlanticcouncil . Whether energy infrastructure protection and diversification expenditures qualify under this category could significantly affect burden-sharing calculations, particularly for allies dependent on Middle Eastern hydrocarbon supplies.
The US-Iran conflict reshapes NATO burden-sharing along multiple dimensions:
First, the conflict reinforces the Trump administration's strategic logic that regional powers must assume primary responsibility for their neighborhoods. The 2025 National Security Strategy states that "America will always have core interests in ensuring that Gulf energy supplies do not fall into the hands of an outright enemy, that the Strait of Hormuz remain open," but frames these as interests to be pursued through burden-sharing networks where the US serves as "convener and supporter" rather than primary provider[PDF] National Security Strategy | The White Housewhitehouse . Gulf states' military participation in operations and absorbing of attacks on their territory demonstrates this burden-shifting model in action.
Second, the conflict exposes the limits of burden-sharing through spending targets alone. Spain's exemption, Germany's military abstention despite supportive rhetoric, and France's limited engagement demonstrate that GDP percentages do not translate directly into operational participation. Former Lithuanian Foreign Minister Gabrielius Landsbergis warned that "securing spending promises under pressure may mean creative accounting, not greater security"—"if nothing is being done, then we're not safer and actually we're in more danger because we're just pretending"Ahead of NATO summit: Spain refuses to raise defense spending to 5% of GDP | DW Newsyoutube .
Third, the attack on UK bases without Article 5 invocation establishes a precedent where attacks on allied forces in non-Article 6 geographies do not automatically trigger collective defense deliberations. This creates asymmetric risk: allies hosting US forces in the Middle East bear retaliation risk while collective defense mechanisms remain geographically constrained.
Fourth, the demonstrated threat to European territory—both through actual strikes on Cyprus and explicit Iranian threats against European cities—may eventually bring Middle East contingencies within the scope of territorial defense planning, potentially requiring doctrinal revision to address ballistic missile threats originating from the region.
Fifth, the coincidence of the Iran conflict with the 2027 European defense responsibility deadline intensifies pressure on both sides of the Atlantic. European allies face simultaneous demands to increase spending toward 5% of GDP, develop capabilities to replace US contributions, and potentially engage in Middle East operations—all while domestic fiscal constraints and public opinion remain significant obstacles.
The 2026 National Defense Strategy's description of allies as "freeloading dependents" facing "shortfalls from their leaders' own irresponsible choices" signals a hardening American position that the Iran conflict—requiring sustained US military commitment outside Europe—is likely to reinforceThe 2026 National Defense Strategy by the Numbers: Radical Changes, Moderate Changes, and Some Continuitiescsis . As stated in that document, "managing" Russia is now seen as a European responsibility with the United States as backup, given that non-US NATO members collectively have 13 times the GDP of RussiaThe 2026 National Defense Strategy by the Numbers: Radical Changes, Moderate Changes, and Some Continuitiescsis .
The ultimate trajectory depends on whether the Iran conflict remains a bilateral US-Israeli operation with European peripheral support, or whether escalation—particularly Iranian strikes on European soil—transforms it into an alliance-wide challenge demanding doctrinal adaptation and unified response. As Secretary General Rutte emphasized amid the crisis: "This is no time to be complacent; all allies have to do more"NATO not involved in US-Israeli war on Iran: Rutte - TRT Worldtrtworld +2.