Who Controls the Strait of Hormuz Under International Law?
- Edmarverson A. Santos
- 3 days ago
- 26 min read
Introduction
Competing claims by Iran and the United States over who controls the Strait of Hormuz have turned a strategic dispute into a legal one. In August 2026, President Donald Trump stated that the Strait was open, while Tehran maintained that it remained closed and commercial traffic was still severely disrupted (Reuters, 2026). The control of the Strait of Hormuz cannot be resolved by asking which State possesses the greater military capability. Territorial sovereignty, jurisdiction, navigation rights, operational sea control, and the capacity to disrupt shipping are separate forms of authority and power.
Iran and Oman are the two States bordering the navigational corridor through Hormuz. Under the structure reflected in Article 34 of the United Nations Convention on the Law of the Sea (UNCLOS), the legal regime governing international straits does not change the status of the waters or displace the sovereignty and jurisdiction of the bordering States. That sovereignty is nevertheless exercised subject to the applicable rules governing passage through international straits (United Nations, 1982). The result is a divided legal order: Iran and Oman retain territorial authority, but neither possesses unlimited discretion over international navigation.
Treaty status complicates the analysis. Oman is a party to UNCLOS, whereas Iran signed the Convention in 1982 but has never ratified it, and the United States also remains a non-party (United Nations Treaty Collection, 2026). Iran stated at signature that the right of transit passage in Article 38 was among the provisions it regarded as the product of negotiated compromise rather than necessarily as pre-existing customary international law. The legal position of non-parties must consequently be distinguished from the treaty obligations binding Oman, particularly where the broader features of transit passage are concerned.
Customary international law nonetheless imposes important limits on coastal-State control. In Corfu Channel, the International Court of Justice recognized that, in peacetime, warships may exercise innocent passage through straits used for international navigation between two parts of the high seas, without prior authorization from the coastal State, provided the passage remains innocent (ICJ, 1949). That judgment preceded the broader UNCLOS regime of transit passage and cannot be treated as authority for every feature later included in Part III, such as overflight or navigation by submarines in their normal mode.
Military dominance belongs to a different legal category. A State may be capable of patrolling shipping lanes, escorting vessels, maintaining surveillance, or denying an adversary effective use of a maritime area without acquiring sovereignty over it. Iran may retain territorial title while losing operational freedom in particular waters; the United States may exercise substantial naval control without obtaining coastal-State jurisdiction. The central legal question is accordingly not who can impose the greatest degree of force at a given moment, but which forms of authority international law recognizes and where their limits lie.
1. What Control of the Strait of Hormuz Means in Law
The control of the Strait of Hormuz cannot be reduced to a single legal status. The law of the sea distributes authority among coastal States, flag States, foreign vessels, and other users according to the legal character of the waters and the activity concerned. Sovereignty, jurisdiction, passage rights, and military power may overlap geographically without producing a single State entitled to govern the Strait as a whole.
This distinction is especially important in Hormuz because legal authority and practical influence may point in different directions. Iran and Oman possess coastal rights that the United States does not. Foreign vessels possess navigation rights that do not depend entirely on the political preferences of either coastal State. Military forces may meanwhile alter the practical conditions under which those rights can be exercised. The relevant question is consequently which legal power or factual capacity is being described when a State claims “control.”
1.1 Sovereignty, jurisdiction, and legal entitlement
Sovereignty supplies the territorial basis for coastal authority. Under Article 2 of UNCLOS, coastal-State sovereignty extends beyond land territory and internal waters to the territorial sea, including its airspace, seabed, and subsoil. In an international strait, Article 34 preserves the legal status of those waters and the sovereignty or jurisdiction of the bordering States while making their exercise subject to the applicable regime of passage and other rules of international law (United Nations, 1982).
Jurisdiction is narrower than sovereignty. It concerns particular powers that a State may exercise over conduct, vessels, persons, or activities. A merchant ship passing through another State’s territorial sea does not cease to be subject to its flag State merely by entering those waters, but flag-State authority is not necessarily exclusive there. Coastal jurisdiction, internationally protected passage rights, and rules concerning the status or immunity of particular vessels can operate at the same time.
Navigation rights create another form of legal entitlement. They permit specified uses of maritime space without transferring governmental authority to the State whose ship or aircraft exercises them. A foreign vessel entitled to passage through an international strait acquires neither territorial title nor a general power to regulate other users. The coastal State likewise retains sovereignty even where international law restricts how that sovereignty may be exercised against passing traffic.
The legal arrangement is consequently functional rather than hierarchical. Different actors may possess different rights over the same movement through the Strait, and the existence of one entitlement does not extinguish the others.
1.2 Sea control and maritime denial
Military influence must be analyzed separately. For present purposes, sea control describes the practical ability of an actor to use a defined maritime area for its own purposes while limiting an adversary’s ability to interfere. Sea denial requires less comprehensive dominance: an actor may make navigation dangerous, costly, or operationally difficult without controlling the area continuously.
These conditions are geographical and temporary. Naval patrols, surveillance, escorts, mine countermeasures, shore-based weapons, drones, submarines, and other capabilities may affect which actor can operate safely at a particular time. Commercial decisions may also be shaped by the perceived risk of attack or seizure even when no State possesses continuous military command of the waterway.
Military advantage does not determine territorial status. A coastal State can retain sovereignty despite losing practical freedom of action in part of its territorial sea. A foreign navy can possess substantial freedom of movement without acquiring the jurisdiction of the coastal sovereign. The distinction between legal authority and maritime power provides the basis for assessing the competing claims made by Iran and the United States.
2. Competing U.S. and Iranian Claims of Control
The present dispute illustrates how different meanings of control can coexist. In August 2026, U.S. President Donald Trump publicly claimed that the United States exercised “total control” over the Strait, while Iranian officials described Hormuz as being under Iranian control and management. Iranian military authorities also asserted that passage depended on authorization, even as the United States maintained that the waterway was open (Reuters, 2026).
Those statements should not be treated as equivalent legal claims. A U.S. assertion of control can refer to naval presence, surveillance, escort capacity, or the ability to contest interference with shipping. Iran can invoke its position as a coastal State while also relying on military proximity and the capacity to impose substantial risks on vessels operating near its coast. Each side may consequently exercise a form of influence without acquiring the forms of authority possessed by the other.
Commercial shipping demonstrates the difference between legal entitlement and practical use. Traffic through Hormuz remained severely disrupted in August 2026 despite U.S. statements that the Strait was operational, with many operators continuing to avoid the route because of security risks (Reuters, 2026). Reduced traffic is evidence of danger and coercive influence. It does not establish that Iran has acquired exclusive legal authority over navigation, just as a successful U.S. escort operation would not establish American sovereignty.
2.1 What a U.S. claim of control can mean
The strongest meaning of a U.S. control claim is operational rather than territorial. American forces may be capable of maintaining a naval presence, monitoring maritime movements, escorting designated vessels, protecting particular transits, and challenging attempts to interfere with navigation. The degree of actual control depends on conditions in a defined area and period rather than on general assumptions about the relative strength of the U.S. Navy.
The United States has no coastal sovereignty over Hormuz. Its legal position instead rests on navigation rights and on the longstanding U.S. view that the transit-passage regime reflected in UNCLOS forms part of customary international law. That position includes the claim that warships may navigate international straits in their normal mode and that military aircraft possess corresponding rights of overflight. The fact that the United States regards those rules as customary law does not itself resolve the customary-law question, particularly where other States have objected to aspects of the modern transit-passage regime.
Navigation rights must also be distinguished from unilateral enforcement authority. Corfu Channel provides an important illustration. The International Court of Justice recognized a customary peacetime right for warships to pass innocently through straits used for international navigation between two parts of the high seas without prior coastal authorization. The Court nevertheless held that Britain’s subsequent minesweeping operation in Albanian territorial waters, undertaken without Albania’s consent, violated Albanian sovereignty (ICJ, 1949).
The principle is directly relevant to contemporary assertions of U.S. control. A right to navigate does not automatically supply a legal basis for coercive action within another State’s territorial waters. Measures involving force, seizure, minesweeping, or comparable enforcement require an independent legal justification under the applicable international-law regime.
2.2 What an Iranian claim of control can mean
Iran’s position combines coastal sovereignty with geographical and military advantage. The country borders the northern side of Hormuz, placing Iranian territory and military assets close to the principal routes used by international shipping. That proximity can provide significant leverage even against a naval power possessing superior capabilities across the wider region.
Current Iranian claims have gone beyond the assertion of ordinary coastal jurisdiction. Iranian officials have stated that the Strait is under Iranian control and management, while military authorities have claimed a power to require authorization for passage (Reuters, 2026). Such statements must be separated from the legal rules that actually govern navigation. An assertion of authority by a coastal State is not equivalent to international recognition of that authority.
Iran may also influence shipping without administering the Strait in a legal sense. The ability to threaten vessels, increase insurance and security costs, deter operators, or interrupt particular movements can produce substantial practical effects. Those effects demonstrate coercive capacity. They do not determine the extent of Iranian sovereignty or establish a general entitlement to regulate international navigation beyond the powers recognized by international law.
3. Legal Authority in Hormuz Is Divided
The physical geography of the Strait is central to its legal structure. Iran forms the northern coast, while Oman’s Musandam Peninsula lies on the southern side. Both coastal States claim territorial seas extending up to 12 nautical miles, and the narrow navigational corridor through Hormuz lies within territorial seas rather than along an ordinary high-seas route.
This does not internationalize the waters themselves. Iran and Oman retain sovereignty over their respective territorial seas. The special character of Hormuz arises because those territorial waters form a strait used for international navigation, bringing into operation rules that protect passage while preserving the underlying territorial status of the waters.
The result is a divided allocation of authority. Coastal sovereignty remains legally significant, but it does not answer every question concerning the movement of foreign ships and aircraft. International passage rights operate within, rather than outside, the territorial framework.
3.1 Iran and Oman as the coastal sovereigns
Any account that treats Iran as the sole coastal authority over Hormuz is incomplete. Oman’s Musandam Peninsula gives it a territorial position on the southern side of the Strait, with corresponding coastal-State powers in Omani waters. The legal geography of Hormuz is thus not reducible to a bilateral contest between Iran and the United States.
Navigational management has long reflected the presence of both coastal States. Iran and Oman jointly proposed the Traffic Separation Scheme adopted by the International Maritime Organization in 1968, creating an internationally coordinated system for organizing vessel movements through the Strait. The scheme concerns navigational safety and traffic organization; it does not create sovereignty or transfer jurisdiction to the IMO.
The distinction has become especially visible during the 2026 conflict. Temporary IMO-supported arrangements have allocated operational responsibility for a northern route to Iran and a southern route to Oman as part of measures intended to manage traffic and deconfliction. Those arrangements respond to current security conditions and do not alter the territorial status of the Strait. The existing Traffic Separation Scheme has not been used normally under that temporary framework because of reported mine risks (IMO, 2026).
Oman’s role consequently illustrates why navigational management should not be confused with ownership. Both coastal States may participate in organizing maritime traffic while remaining bound by the legal limitations applicable to the exercise of coastal authority.
3.2 Navigation rights as limits on coastal authority
Article 34 of UNCLOS captures the relationship between territorial status and international navigation. The regime of passage through international straits does not otherwise alter the legal status of the waters forming those straits or the sovereignty and jurisdiction of the bordering States over the waters, airspace, seabed, and subsoil. Their sovereignty and jurisdiction are nonetheless exercised subject to Part III of the Convention and other applicable rules of international law (United Nations, 1982).
For States bound by UNCLOS, that structure is developed through the transit-passage regime. Article 38 recognizes navigation and overflight for continuous and expeditious transit through qualifying international straits, while Article 44 requires bordering States not to hamper transit passage and provides that there shall be no suspension of it (United Nations, 1982).
These rules do not turn Hormuz into an international commons or remove Iran and Oman from the legal equation. They limit particular exercises of coastal authority because the waters perform an international navigational function. A vessel exercising passage does not depend on a discretionary grant of access from the coastal State where the applicable legal regime confers the right independently.
The distinction is important for claims of control. Territorial sovereignty identifies who possesses authority over the waters as territory. International straits law determines how far that authority may be exercised against international navigation.
3.3 Treaty obligations and customary law
The treaty position differs among the principal States involved. Oman is a party to UNCLOS. Iran signed the Convention in 1982 but has not ratified it, while the United States remains a non-party (United Nations Treaty Collection, 2026). Part III consequently binds Oman as treaty law, whereas the position of Iran and the United States requires separate consideration of customary international law.
Iran addressed this distinction when it signed UNCLOS. Its interpretative declaration stated that certain provisions of the Convention resulted from negotiated compromise and were not necessarily codifications of pre-existing customary law. Iran specifically identified the Article 38 right of transit passage among those provisions (United Nations Treaty Collection, 2026).
The United States has maintained the broader position that transit passage through international straits reflects customary international law, including navigation by submarines in their normal mode and overflight by military aircraft. That position is supported by substantial State practice and legal commentary, but it should not be treated as uncontested merely because it has been consistently advanced by major maritime powers.
Earlier customary law establishes a firmer minimum. In Corfu Channel, the ICJ recognized that, in peacetime, warships have a right of innocent passage through straits used for international navigation between two parts of the high seas without prior authorization from the coastal State, provided the passage remains innocent (ICJ, 1949). The modern UNCLOS regime goes further by expressly protecting transit passage, normal-mode navigation, and overflight.
For Hormuz, the distinction prevents two opposite errors. Iran’s non-ratification does not by itself establish an unrestricted coastal power to determine whether international passage exists. Nor should every provision of UNCLOS Part III automatically be presented as binding Iran on an identical customary basis without examining the status of the particular rule. The legal allocation of control must remain sensitive to the difference between treaty obligations, established custom, and contested claims concerning the broader transit-passage regime.
4. Oman’s Legal and Operational Role in Hormuz
Oman’s significance in Hormuz goes beyond its territorial position on the southern side of the Strait. As a UNCLOS party and a State bordering an international strait, Oman exercises coastal jurisdiction within a legal framework that simultaneously preserves its sovereignty and constrains how that sovereignty may affect international navigation. Its position helps illustrate why legal authority over Hormuz cannot be reduced to either Iranian coastal power or U.S. military capability.
The more important question is how Oman exercises that authority. Maritime safety, traffic organization, routeing, and cooperation with international institutions fall within a regulatory sphere that is distinct from territorial ownership. Omani participation in such arrangements demonstrates that practical management of Hormuz is distributed among coastal and international actors rather than concentrated in a single State.
Oman has also adopted declarations reflecting a security-conscious interpretation of maritime passage. Those declarations are legally relevant because they reveal the Sultanate’s understanding of its coastal interests, but their effect remains subject to the Convention that Oman accepted on ratification. They cannot be treated as unilateral amendments to UNCLOS.
4.1 Oman’s position in the navigational corridor
The internationally organized movement of vessels through Hormuz has long involved both Oman and Iran. The two States jointly proposed the Traffic Separation Scheme adopted by the International Maritime Organization in 1968. That scheme separates opposing flows of commercial traffic and structures vessel movements through a confined and heavily used navigational corridor (IMO, 2026a).
Oman’s involvement reflects its status as a coastal State rather than a delegated power to administer international shipping. Within the applicable legal regime, it may exercise regulatory authority connected with maritime safety, traffic organization, pollution prevention, and other recognized coastal interests. Such competence coexists with the navigation rights of foreign vessels passing through the Strait.
The 2026 security crisis made this distribution of functions particularly visible. Under the IMO-supported evacuation framework, an alternative southern route was established through Omani waters, with Oman assuming operational responsibilities for vessel movements using that route. A corresponding northern route involved Iranian waters. The arrangements were adopted as temporary responses to exceptional security conditions and were later paused following further attacks on shipping (IMO, 2026b).
4.2 Routing and traffic management are not ownership
UNCLOS Article 41 provides a legal mechanism for States bordering straits to designate sea lanes and prescribe traffic-separation schemes where necessary to promote safe passage. Proposed schemes are referred to the competent international organization, which may adopt only those agreed with the States bordering the strait. This procedure recognizes both coastal-State participation and the international interest in safe navigation through major maritime routes (United Nations, 1982).
Traffic management consequently represents regulatory authority directed toward navigation rather than a division of sovereign ownership. A route passing through Omani waters may be subject to Omani safety regulation within the limits of international law, while IMO adoption provides international coordination. Neither element gives the international organization jurisdiction over the territorial sea, nor does it grant Oman authority beyond its lawful coastal competence.
The temporary 2026 arrangements reinforce this distinction. Iran and Oman were assigned operational responsibilities for separate routes under an emergency framework, while the established Traffic Separation Scheme was not being used normally because of reported mine risks (IMO, 2026b). Such arrangements can change quickly as navigational conditions change. They describe how traffic is managed at a particular moment, not the permanent legal status of Hormuz.
4.3 Oman’s declarations under UNCLOS
Oman accompanied its participation in UNCLOS with declarations concerning security and passage. At signature, it stated its understanding that Articles 19, 25, 34, 38, and 45 did not prevent a coastal State from taking appropriate measures necessary to protect its peace and security. Article 38 is particularly relevant because it governs the right of transit passage through qualifying international straits (United Nations Treaty Collection, 2026).
Upon ratification in 1989, Oman also declared that innocent passage by foreign warships through its territorial waters required prior permission. Its declaration addressed submarines exercising innocent passage by requiring them to navigate on the surface and show their flag and imposed additional requirements concerning certain nuclear-powered and hazardous vessels (United Nations Treaty Collection, 2026).
Those declarations do not operate independently of the Convention. Article 309 prohibits reservations unless UNCLOS expressly permits them, while Article 310 allows declarations only where they do not purport to exclude or modify the Convention’s legal effect. Oman’s recorded position may inform the interpretation of its security concerns, but it cannot unilaterally displace obligations accepted under Part III.
The distinction between innocent passage and transit passage is decisive. Oman expressly formulated its 1989 warship requirement in relation to innocent passage. It should not automatically be read as establishing a prior-authorization requirement for vessels entitled to transit passage through an international strait. Any broader interpretation would have to be reconciled with Articles 309 and 310 and with Oman’s treaty obligations under Part III.
5. Authority Over Ships and Aircraft in the Strait
Authority over the users of Hormuz is distributed rather than absolute. A vessel entering Iranian or Omani territorial waters retains its nationality and legal relationship with its flag State, while coastal-State powers arise from territorial sovereignty and the particular rules governing passage. The type of vessel and the applicable passage regime affect the balance between those forms of jurisdiction.
This becomes especially important for warships, government vessels, submarines, and aircraft. Their status cannot be inferred from the general powers that a coastal State may exercise over ordinary commercial shipping. Sovereign immunity and the broader rights associated with transit passage alter the legal relationship between the user and the State bordering the Strait.
The result is a functional allocation of authority. One State may possess jurisdiction for navigation safety, another remains internationally responsible for its State vessel, and the passage regime itself limits interference with lawful transit. Claims that a State “controls” all vessels using Hormuz consequently obscure several separate jurisdictional relationships.
5.1 Merchant vessels and flag-State jurisdiction
Merchant vessels remain legally connected to their flag State while passing through another State’s territorial waters. Entry into a territorial sea does not terminate flag-State jurisdiction, although coastal-State jurisdiction may also arise. The extent of coastal authority depends on the applicable legal rule and the conduct at issue.
Under the ordinary innocent-passage regime, UNCLOS limits coastal interference with foreign merchant ships and regulates the circumstances in which criminal and civil jurisdiction may be exercised over vessels merely passing through the territorial sea. Those restrictions reflect the broader principle that territorial sovereignty does not automatically produce unrestricted jurisdiction over every event occurring on board a foreign ship (United Nations, 1982).
For transit passage, Article 42 allows States bordering straits to regulate specified matters, including navigational safety, pollution, fishing, and certain customs, fiscal, immigration, and sanitary issues. Such laws may not discriminate among foreign ships or have the practical effect of denying, hampering, or impairing transit passage (United Nations, 1982).
A merchant vessel using Hormuz is consequently subject to a combination of flag-State authority, lawful coastal regulation, and internationally protected navigation rights. The relevant legal question is not which State exercises complete control over the vessel, but which jurisdiction applies to the particular conduct being regulated.
5.2 Warships, submarines, and State vessels
Warships and government ships operated for non-commercial purposes occupy a different legal position because they benefit from sovereign immunity. UNCLOS preserves those immunities while also imposing duties on ships exercising passage. The coastal State’s authority over such vessels cannot simply be equated with its powers concerning privately operated merchant shipping (United Nations, 1982).
The applicable passage regime is critical. Article 30, which permits a coastal State to require a non-compliant foreign warship to leave the territorial sea after disregarding a request for compliance, belongs to the innocent-passage regime in Part II. It should not be treated as the enforcement rule governing warships exercising Part III transit passage through an international strait.
Part III instead addresses State vessels through provisions including Article 42(5). Where a warship, another government ship operated for non-commercial purposes, or a State aircraft acts contrary to Part III or to applicable laws adopted by a State bordering the strait, the flag State bears international responsibility for resulting loss or damage (United Nations, 1982). This structure protects the passage regime while preserving accountability for unlawful conduct.
Submarines illustrate a further distinction. Article 20 expressly requires submarines exercising innocent passage to navigate on the surface and show their flag. Part III contains no equivalent surface-navigation requirement. Article 39 refers to activities incident to the normal modes of continuous and expeditious transit, and the prevailing interpretation of that language, supported by the negotiating history and extensive maritime practice, permits submarines exercising transit passage to remain submerged.
That interpretation should not be overstated. UNCLOS does not expressly state in a separate provision that submarines have a right to submerged transit. The conclusion derives from the structure and language of the transit-passage regime. Its application to Iran also raises the separate customary-law question because Iran is not a party to UNCLOS and has objected to treating Article 38 automatically as pre-existing custom.
5.3 Aircraft and the airspace above the Strait
Aircraft demonstrate one of the clearest differences between innocent passage and transit passage. Innocent passage applies to ships moving through the territorial sea and does not confer a general right of foreign aircraft to cross the sovereign airspace above it. Transit passage expressly encompasses both navigation and overflight through qualifying international straits (United Nations, 1982).
Aircraft exercising transit passage remain subject to legal obligations. Article 39 requires civil aircraft to observe the Rules of the Air established by the International Civil Aviation Organization and requires State aircraft to operate with due regard for navigational safety. Overflight is consequently a protected use of the strait regime rather than an unrestricted freedom to conduct unrelated military activity.
For Oman, the treaty position follows directly from UNCLOS because it is a party. Iran presents a different question. The United States and other maritime powers maintain that the right of transit passage under customary international law includes military overflight, whereas Iran’s recorded position disputes the assumption that Article 38 necessarily codified a pre-existing customary rule.
The distinction is significant because it separates two propositions that are sometimes merged. UNCLOS unquestionably protects overflight as part of transit passage for States bound by the Convention. The extent to which the same rule binds and benefits non-parties must be established through customary international law rather than merely by citing the treaty text.
6. Sea Control, Sea Denial, and Maritime Power
The concepts of sea control and sea denial become useful once the analysis moves from legal entitlement to actual military conditions. They do not determine who possesses sovereignty over Hormuz. Instead, they describe the ability of competing forces to use, protect, or restrict access to maritime space during a specified period and within a specified geographical area.
The current conflict demonstrates why neither concept should be understood in absolute terms. A militarily stronger actor can possess substantial freedom of action without eliminating every threat to shipping. A weaker actor can impose serious risks without possessing the capability to administer or dominate the entire maritime area.
Hormuz is particularly suited to that form of asymmetric contest because its narrow geography concentrates shipping and places vessels close to coastal military capabilities. The strategic question becomes how much freedom each actor can deny or preserve rather than which State can claim permanent military possession of the Strait.
6.1 Iran and the capacity for sea denial
Iran’s position gives it substantial opportunities to complicate navigation without establishing comprehensive sea control. Mines, shore-based missiles, drones, fast attack craft, and other systems can threaten vessels moving through a confined route and force commercial or military operators to adjust their behavior.
The 2026 conflict demonstrates the practical consequences of such risk. IMO has documented repeated attacks on commercial shipping, damage to vessels, fatalities among seafarers, and reported mine hazards affecting the use of established routes. These facts establish a severely degraded navigational environment without, by themselves, resolving responsibility for every individual incident (IMO, 2026c).
Commercial behavior provides another indication of sea-denial effects. Vessels may delay voyages, seek escorts, use alternative arrangements, or avoid the Strait because the expected cost of transit has become unacceptable. Such decisions can give Iran significant coercive leverage even where the precise military source of every disruption remains disputed.
That influence should not be equated with continuous military command of Hormuz. Sea denial can succeed precisely because it does not require the actor to control every movement. The ability to impose credible risk on a critical navigational corridor may be strategically significant even while an adversary retains substantial freedom to conduct military operations.
6.2 U.S. operational sea control
U.S. military activity demonstrates a different form of maritime power. In April 2026, U.S. Central Command stated that American forces had begun setting conditions for mine-clearance operations and for the establishment of a navigable passage through Hormuz (CENTCOM, 2026a). The statement is evidence of the operation officially claimed by the United States, not independent proof of the extent to which the objective had already been achieved.
In May, CENTCOM reported that U.S. destroyers transiting the Strait intercepted missiles, drones, and small boats before continuing their passage (CENTCOM, 2026b). Such incidents indicate an ability to protect particular military movements and contest threats in defined circumstances. Because CENTCOM is itself a belligerent command, its account should be used as an official statement concerning U.S. operations rather than treated as neutral verification of every operational detail.
The United States also possesses capabilities for surveillance, escort, air and naval protection, and mine countermeasures that can support sea control in particular areas and periods. The relevant concept remains conditional: protecting one transit or establishing temporary freedom of movement does not establish uninterrupted command over all commercial and military activity in the Strait.
Commercial traffic remained heavily disrupted in August 2026 despite U.S. statements that Hormuz was open (Reuters, 2026). That fact demonstrates that normal maritime use had not been fully restored. It supports the conclusion that U.S. operational freedom can coexist with continuing threats and commercial caution, but it does not by itself establish which actor was responsible for every remaining disruption.
The strategic balance is consequently better described as a contest between substantial U.S. capacity for sea control and Iran’s continuing ability to generate sea-denial effects. Those military conditions can change rapidly. Neither changes the underlying territorial sovereignty of Iran and Oman nor determines, by itself, the legal rights of ships and aircraft using the Strait.
7. Legal Limits of U.S. and Iranian Operational Control
The preceding distinction between sea control and legal authority becomes decisive when military power is used to protect or restrict navigation. A State may possess the practical capacity to escort vessels, interrupt shipping, or dominate a particular maritime area without acquiring a general competence to govern that area.
For the United States, operational freedom does not convert navigation rights into coastal jurisdiction. Iran likewise cannot derive an unlimited authority over international passage merely from its geography or capacity to impose military risk. Each measure must be assessed under the legal regime governing the conduct in question.
The analysis must also separate the law of the sea from the law governing force. A navigation entitlement answers whether a ship or aircraft may lawfully use the Strait. It does not by itself answer whether another State may employ coercive measures to secure that use.
7.1 Navigation Rights and Coercive Enforcement
International passage rights do not create a general enforcement power. A State invoking freedom of navigation cannot rely on that right alone to justify attacks, forcible seizure, minesweeping in foreign territorial waters, or other coercive measures. Each operation requires an independent legal basis appropriate to its character.
Under the UN Charter, the prohibition on the threat or use of force remains the starting point. Foreign military operations may be lawful where valid consent has been given by the territorial State, where the Security Council has authorized the relevant action, or where the requirements of individual or collective self-defense are satisfied. Self-defense must in particular remain subject to necessity and proportionality (United Nations, 1945).
Other maritime measures may arise under different rules. Vessel seizure, belligerent capture, law-enforcement action, and military attack are not legally interchangeable simply because each can affect shipping. The existence of a passage right through Hormuz does not eliminate the need to identify the separate jurisdictional or military-law basis for the measure used to protect or interfere with that passage.
7.2 Corfu Channel and the Limits of Self-Help
The Corfu Channel judgment remains relevant because it addressed the relationship between navigation and unilateral enforcement directly. The International Court of Justice recognized a customary peacetime right for warships to pass innocently through straits connecting two parts of the high seas and used for international navigation, without prior authorization from the coastal State (ICJ, 1949).
The Court did not extend that right into a general power of self-help. Britain later conducted minesweeping operations in Albanian territorial waters without Albania’s consent, arguing in part that its actions were necessary to secure evidence and address the danger to navigation. The Court held that the operation violated Albanian sovereignty (ICJ, 1949).
The distinction remains applicable to Hormuz. A State may be entitled to navigate and may possess military capabilities capable of protecting particular movements. Neither proposition supplies a general right to police Iranian or Omani territorial waters. Coercive action must stand on an independent legal justification rather than being treated as an automatic consequence of freedom of navigation.
7.3 Sovereignty Under Military Dominance
Territorial sovereignty does not normally follow shifts in battlefield advantage. A foreign navy may acquire substantial freedom of action in another State’s territorial sea while the legal title to those waters remains with the coastal State. Effective military influence and sovereignty answer different questions.
The same principle operates when the coastal State loses practical control. Iran could remain sovereign over Iranian territorial waters even if foreign forces temporarily prevented Iranian naval units from operating effectively there. Oman’s sovereign rights are similarly unaffected merely because another State possesses stronger military capabilities in surrounding waters.
International law has long rejected the proposition that temporary military control by itself transfers sovereign title. The International Court of Justice has also reaffirmed, in the context of belligerent occupation, that effective foreign control is temporary in character and cannot itself confer sovereignty (ICJ, 2024). That broader principle is sufficient here; the specialized and unsettled question of whether territorial seas can themselves be “occupied” need not determine the legal status of Hormuz.
8. Sovereignty and Control During Armed Conflict
Armed conflict changes the rules governing military activity at sea, but it does not replace the law of international straits with a simple rule of belligerent control. Naval warfare rules may govern attacks, mines, blockade, interception, and neutral shipping while the underlying territorial status of Iranian and Omani waters remains unchanged.
The distinction is especially important because military conditions in Hormuz can change rapidly. A route may be usable for one operation and dangerous shortly afterward. Such changes affect sea control and sea denial, not sovereign title.
The law applicable during hostilities is also fragmented by function. Rules governing transit through international straits, the conduct of naval hostilities, neutral waters, and the legality of resorting to force continue to address separate legal questions.
8.1 Naval Warfare Rules in Hormuz
The San Remo Manual states that passage rights applicable through international straits in peacetime continue during armed conflict, including transit by surface ships, submarines, and aircraft where the relevant regime applies (San Remo Manual, 1994). The Manual is an influential expert restatement rather than a treaty, and its provisions should not automatically be treated as independently proven customary law.
The status of neutral coastal waters adds another limit. Under the Manual, the territorial waters of a neutral State are neutral waters, in which hostile actions are prohibited, while applicable rights of passage through international straits remain preserved. This distinction can become directly relevant to Omani waters if Oman is neutral in a conflict involving other States.
Mine warfare is also constrained by the international character of straits. The San Remo Manual provides that mines must not have the practical effect of preventing transit passage through international straits unless safe and convenient alternative routes are available. Even during hostilities, military control of a chokepoint is not legally equivalent to an unrestricted right to deny its international navigational function.
8.2 Blockade, Interdiction, and Territorial Status
Blockade provides a clear example of the difference between military control and sovereignty. The modern law of naval blockade, as reflected in the San Remo Manual, requires declaration and notification, effectiveness, impartial application, and compliance with humanitarian limits. A blockade also may not bar access to the ports and coasts of neutral States (San Remo Manual, 1994).
Interdiction, exclusion measures, attacks on vessels, and other forms of naval control raise distinct legal questions concerning status, targeting, neutrality, proportionality, precautions, and the applicable treaty or customary rules. Describing all of these measures as evidence that a belligerent “controls” the Strait obscures the legal basis and limits of each operation.
Even a highly effective wartime restriction on shipping would not make the enforcing belligerent sovereign over Hormuz. It would establish a temporary capacity to regulate or deny maritime movement under the conditions of armed conflict. Territorial title would continue to depend on the underlying sovereignty of Iran and Oman, not on which belligerent happened to dominate the waterway militarily.
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Conclusion
No single State controls the Strait of Hormuz in every legally relevant sense. Iran and Oman retain sovereignty over their respective territorial waters, while international law limits how coastal authority may be exercised against passage through a strait used for international navigation. The precise content of those navigation rights depends in part on treaty obligations and, for non-parties such as Iran and the United States, on the applicable rules of customary international law.
Military power produces a separate distribution of influence. Iran can possess substantial sea-denial capacity and coercive leverage without acquiring exclusive authority over international navigation. The United States can achieve significant sea control in defined areas and periods without becoming a coastal State or obtaining sovereign jurisdiction over the Strait. Armed conflict activates additional rules governing naval hostilities, but it does not convert operational dominance into territorial title.
The most accurate answer is consequently divided rather than singular. Iran and Oman possess territorial authority within their respective maritime areas; ships and, under the applicable transit-passage regime, aircraft may possess internationally protected rights of passage; jurisdiction over particular vessels depends on their status and conduct; and military control remains contingent. Claims that Iran, the United States, or any other State exclusively “controls” Hormuz are legally incomplete unless they specify which of these forms of authority is being asserted.
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