The U.S.-Iran War: Fighting From ‘Neutral’ Territory

On March 9, Reuters reported Iranian missile strikes on the U.S.-operated Al Udeid base in Qatar and drone attacks aimed at Al Dhafra in the United Arab Emirates (UAE) and Juffair in Bahrain. Qatar condemned the strikes as attacking its territory even as it continued to deepen its defense relationship with the United States. At the same time, the UAE, Saudi Arabia, and Kuwait all claimed they were not parties to the U.S.-Iran conflict. The UAE “reaffirmed [its] commitment to not allowing its airspace, territory, or waters to be used in any hostile military actions against Iran, and to not providing any logistical support in this regard.” Saudi Arabia told Iran a month before the war began that it would not allow its airspace or territory to be used for military actions against Iran. And Kuwait similarly said that it was not a party to any regional conflict and would not allow its territory to be used for launching attacks.

These statements may or may not be sincere. But perhaps more urgently, the pertinent question is whether they are legally sustainable when foreign bases on a state’s soil are being used to support a belligerent’s attacks in a war.

The U.S.-Iran war has exposed a fundamental tension in neutrality law: When a state hosts permanent foreign military bases, it struggles to credibly claim neutrality, while the opposing belligerent faces uncertainty about which targets it can lawfully attack.

The Neutrality Doctrine

Neutrality law is centered on a specific premise: Neutral territory is not supposed to become a platform for a belligerent’s military operations, and neutral states must prevent such use of their territory. The modern U.S. military basing network has become a stress test for this rule. These bases are permanent and integrated into a larger network of warfare with pre-positioned forces, using host-state infrastructure, engaging in shared intelligence and logistical processes, and enabling real-time military operations. In doing so, they strain neutrality law’s assumption that states can realistically separate themselves from a conflict. For example, in Northeast Asia, U.S. forces operate from permanent bases in Japan and South Korea, including Camp Humphreys, the largest U.S. overseas base, while participating in increasingly integrated command arrangements, joint exercises, ballistic missile defense training, and real-time data-sharing systems with host-state forces.

Much of neutrality law is codified within Hague V and Hague XIII. While Iran and the U.S. are signatories to these conventions, the Gulf states most directly implicated in the conflict, including Qatar, the UAE, Bahrain, Kuwait, and Saudi Arabia, are not . However, many scholars argue that neutrality law is accepted as customary international law, binding on all states. Under the provisions of Hague V, neutral territory is inviolable, allowing for no movement of troops or war supplies across that territory. Under Hague XIII, states cannot supply warships, ammunition, or war material (including intelligence or logistics) to belligerents. Both conventions require the neutral states to act to disallow such prohibited acts or the belligerent use of their territory.

The key idea in the context of the U.S.-Iran war is that neutrality is not limited to an ad hoc “wartime permission.” In other words, the implicit argument about permanent bases is that they are agreed to in peacetime, so there is no affirmative action during wartime that a neutral state is taking that would break neutrality. However, Hague V, Article 3 prohibits not only building wartime installations on neutral territory but also “us[ing] any installation of this kind established by [the belligerent] before the war” for military purposes.

In this context, what does the term “use” mean in 2026?

Jeremy Davis’s work on neutrality and bilateral defense treaties offers some answers. He describes neutrality as imposing duties of non-participation and prevention. He reads “non-participation” as refraining from providing belligerents with “with forces, supplies, or other forms of support [including] logistics services, including basing and re-supply points.” Meanwhile, “prevention,” according to Davis, is a neutral state’s duty to resist the belligerent’s use of that state’s territory or resources. These categories apply neatly to the aforementioned U.S. air bases in the Gulf states. For example, the Combined Air Operations Center at Al Udeid in Qatar is a command-and-control hub for logistical operations throughout the region. Shortly before the Iran war, U.S. Central Command even announced a new coordination cell at Al Udeid “to enhance integrated air and missile defense.” In Bahrain, the U.S. naval installation supports forward operations and responsiveness. Meanwhile, the U.S. uses its operational command post on Camp Arifjan, Kuwait, as a logistics and command hub.

The violation of neutrality law occurs when a host state allows a base (built during peacetime) to be used during wartime in the way described by Davis above. If a state genuinely prevents its territory from being used for offensive purposes, it retains its neutrality. But if a host state affirmatively allows its territory to be used as a base for strikes, it veers much closer to a classic violation of neutrality. Reading the aforementioned statements of neutrality from Saudi Arabia, Kuwait, and the UAE, the Gulf states seem aware of this legal distinction. Their consistent framing suggests a host state attempting to avoid a violation of neutrality, such as the UAE’s reaffirmation that its territory or airspace will not “be used in any hostile military actions against Iran, and [commits] to not providing any logistical support in this regard.” They are trying to walk the line between hosting a base and participating in a conflict. But that distinction is difficult to enforce when the base is permanent. A permanent base already contains foreign troops, equipment, command systems, and logistical infrastructure that can support military operations the moment hostilities begin. Should the base’s owner start these operations once the war begins, the host state has little practical ability to separate itself from the conflict. Most importantly, even if a host state tries to restrict how a foreign base is used, the mere presence of those forces can make the host state a target once the conflict begins.

For example, on April 6, Iran announced that it struck U.S. forces that had relocated to Bubiyan Island in Kuwait, also causing civilian injuries from debris. The attack illustrates that even when a host nation tries to prevent offensive use of its territory, it may still be targeted by the opposing belligerent simply for hosting those forces. In Bahrain, Reuters reported civilian injuries in a residential area tied to a drone strike and interception attempt—showing how interception debris or failed strikes can endanger the very civilians living near the host nation’s defense infrastructure.

Defense: What Is the Host State Allowed to Do

Hosting foreign forces also raises a distinct legal question: How far may the host state go in defending itself—and those forces—without losing neutrality?

Neutrality does not prevent a state from defending itself. If a neutral state is attacked by a belligerent, it has the right to defend itself without losing its neutrality status. In fact, Article 5 of Hague V encourages states to act to defend against violations of neutrality: “A neutral Power must not allow any of the acts referred to in Articles 2 to 4 to occur on its territory.” Modern restatements, such as the HPCR Manual on International Law Applicable to Air and Missile Warfare, say the same, limiting force to what is required to repel the hostile act. Separately, Article 51 of the UN Charter allows a state to act in self-defense “if an armed attack occurs.” In the context of the Iran war, Iranian missiles have targeted U.S. bases in the Gulf states as well as infrastructure such as oil processing facilities, commercial shipping, airports, hotels, and even a desalination plant, causing significant physical and economic damage. Gulf states would likely argue that any reaction to these strikes with force would abide by the laws of neutrality—even if the reaction indirectly benefited U.S. forces—since the state is defending its own territory. But at what point does “defense” translate to “contributing to a belligerent’s military operations”?

U.S. overseas military basing makes it difficult to separate self-defense and participation in a conflict. When host-state systems are integrated with U.S. command networks, as is happening through modern basing, defensive actions can have wider effects beyond the immediate interception. For example, a missile interception by Qatar can save valuable assets such as U.S. refueling aircraft and provide early warning to sustain ongoing air operations. The line between self-defense and support is further blurred because the United States supplies many Gulf states with the air-defense system and interceptors Qatar would likely use in that defensive operation. These kinds of actions then begin to look like a contribution to a belligerent’s military campaign instead of purely territorial defense.

Neutrality is likely not the only important legal lens for determining when a state’s right to defend itself turns into a contribution to a belligerent’s military operations. The law of state responsibility also becomes relevant. Under Article 16 of the International Law Commission’s Articles on State Responsibility, a state that aids or assists another state’s internationally wrongful act is jointly responsible for the act when the assistance is given with knowledge of the circumstances and the act would be wrongful if committed by the assisting state. Although this rule comes from a different area of law, it offers a useful framework for distinguishing incidental assistance from deliberate assistance. Scholarship on Article 16 makes two points worth noting here: First, the required mental element is demanding—“should have known” is not enough; actual knowledge is required. Second, the assistance must make a meaningful contribution to the wrongful act; a merely incidental benefit does not suffice.

The law of state responsibility creates a different kind of legal risk for Gulf states. Even while claiming neutrality, a Gulf state could incur indirect responsibility for aiding or assisting a wrongful U.S. act. For example, consider a Gulf state that permits U.S. forces to operate from its territory and provides logistical or intelligence support for U.S. missions. Even if that state does not itself use force and continues to claim neutrality—which may be at least a plausible argument depending on the extent of its support—it may still bear responsibility under the law of state responsibility if it knowingly contributed to a wrongful U.S. act.

Legal Remedies: What Is Iran Allowed to Do?

The preceding analysis has examined the question from the host state’s perspective—specifically, how far a host state may act before forfeiting its neutral status. The inverse question is equally important: What options does an attacking state have when its adversary is launching operations from ostensibly neutral territory?

Neutrality-era statements, including modern manuals, allow for a form of “self-help” in those cases where a neutral territory is being used by a belligerent and is unable or unwilling to stop the violation. The HPCR manual says that “[i]f the use of the neutral territory or airspace by a Belligerent Party constitutes a serious violation, the opposing Belligerent Party may, in the absence of any feasible and timely alternative, use such force as is necessary to terminate the violation of neutrality.” State-specific interpretations of the law also support this idea. For instance, the Commander’s Handbook on the Law of Naval Operations, a U.S. military manual explaining how international humanitarian law and neutrality law apply to naval operations, makes space for acts of hostilities in neutral waters when used as “self-help enforcement actions against enemy forces in violation of the neutral status of those waters when the neutral State cannot or will not enforce its inviolability.”

The U.N. Charter, in turn, sets a stricter baseline. States cannot use force against another’s territory except in rare cases like self-defense. And if one is to issue an armed attack, it must fall within the charter’s rules, such as necessity and proportionality (the force used must be necessary to repel the attack and proportionate to that defensive objective), meaning that Iran is limited in the scale and scope of its strike, and has to justify that striking the military base is necessary. Article 103 of the charter also provides that if there is a conflict between the charter and earlier rules, the charter takes precedence. In light of this, commentators and practitioners have argued that the charter has superseded and weakened the law of neutrality. For example, the U.K. Manual of the Law of Armed Conflict, the U.K.’s official statement of how international law applies to armed conflict, says “the traditional law of neutrality has been affected by and, to a large extent, superseded by the UN Charter.”

The problem of separating neutrality law and the charter’s restrictions becomes especially clear in the Gulf states. When U.S. forces are stationed in another country, the distinction between striking enemy forces and using force inside a foreign state’s territory begins to collapse. For example, a missile aimed at a U.S. base located inside a Gulf state is, at the same time, a strike on the Gulf state’s soil. That is precisely why host governments have condemned such attacks as violations of their sovereignty, even when the intended target was U.S. personnel or infrastructure, not the host state itself.

Modern basing arrangements deepen this issue. As described above, U.S. forces are not confined to self-contained installations that are cleanly separable from the surrounding country. They are woven in the host state’s territory and infrastructure—drawing on local power grids and transport networks, and operating within shared command and sensor systems. Military activity is also distributed across multiple sites rather than concentrated at a single base. The practical consequence is that an Iranian strike on U.S. forces will almost inevitably take place within the host state’s territory and produce effects that extend beyond the intended military target. The result is a persisting legal tension: Iran may view these bases as legitimate military objectives because they support attacks against it, but striking them still involves using force on the territory of states that claim to remain outside the conflict.

This tension is not entirely new. As far back as the Hague Conventions of 1907, neutrality law has addressed situations in which belligerents sought to use neutral territory for transit, supply, or communication. But those rules were developed in a world where such uses were more sporadic and territorially confined. Modern basing arrangements are different. They create a continuous, integrated presence in which foreign forces, infrastructure, and operations are embedded within the host country. Therefore, the distinction neutrality law tries to draw between belligerent activity and neutral space becomes much harder to maintain.

Where Does This Leave Neutrality?

Neutrality is often treated as a binary status—a state is either neutral or it is a belligerent. But in the modern basing era, that framing obscures more than it clarifies. Neutrality is less a switch a state can flip and more a duty to separate hostile operations—an obligation that becomes progressively harder to fulfill as defense cooperation becomes more integrated. As Hague V’s discussion of preexisting installations illustrates, the peacetime origins of a military base provide no automatic shield: A host state can still violate its neutrality if it fails to take active steps to prevent belligerents from using its soil as a launchpad for attacks.

The host state faces a two-pronged dilemma: It wants the diplomatic, security, and economic benefits that come with hosting U.S. forces, but it also wants to preserve its neutral status should a war break out. The problem is that these two goals pull in opposite directions. The deeper U.S. forces embed themselves in the host state’s territory and infrastructure, the harder it becomes for that state to credibly claim neutrality in a conflict. And the more it is drawn into the conflict, the more likely it is to come under attack—forcing it to decide how vigorously it can defend itself before that defense becomes a belligerent act in its own right.

The belligerent, in this case Iran, faces a mirror-image dilemma. Striking U.S. forces means striking the territory of a state that has not declared itself a party to the conflict, risking violation of the UN Charter. But absorbing the attacks without responding means accepting the military consequences of operations launched from that territory. The legal framework, in other words, leaves both sides with very little room to maneuver.

These dilemmas extend well beyond the U.S.-Iran war context. Permanent overseas basing is not an aberration—it is a defining feature of how modern military power is projected. If the law of neutrality cannot provide workable answers in this setting, then future conflicts involving overseas bases, whether in the Middle East, Eastern Europe, or the Indo-Pacific, will face the same unresolved tensions. And with each such conflict, the gap between the law as written and the war as fought will grow wider.