Somewhere in the 21-mile-wide neck of the Strait of Hormuz, a loaded crude tanker is transiting with its automatic identification system switched off. Its bridge crew is not navigating alone. According to defense and shipping sources familiar with the operations, U.S. naval personnel are providing real-time routing guidance to commercial vessels making the passage, a quiet arrangement that keeps tankers off Iran’s radar while sanctions enforcement and military tensions in the waterway intensify. The practice has not been officially confirmed by the Pentagon, but it aligns with a broader posture the U.S. government has laid out in public documents: treat Iran’s self-appointed toll authority as illegitimate, keep American-linked ships in close contact with the Navy, and prepare for the possibility of Iranian retaliation.
On the other side of that equation, Iran’s Islamic Revolutionary Guard Corps Navy operates a fleet of at least 14 Ghadir-class midget submarines, diesel-electric boats roughly 29 meters long and purpose-built for the shallow, warm waters of the Persian Gulf. The U.S. Office of Naval Intelligence has tracked these vessels for years, noting their ability to lay mines, fire torpedoes, and operate in waters too shallow for most conventional submarines. Whether any Ghadir boats are actively patrolling the strait right now has not been confirmed by U.S. officials on the record, but their known basing at Bandar Abbas, which sits directly on the strait’s northern shore, makes their presence during a period of heightened tension a near-certainty in the assessment of multiple defense analysts.
The collision of these two realities has turned the world’s most important energy chokepoint into a low-visibility standoff with consequences that reach every refinery and fuel pump on the planet.
Washington draws a hard line on Iran’s toll scheme
The legal backbone of the U.S. posture is unusually explicit. The Treasury Department’s Office of Foreign Assets Control published a direct prohibition stating that U.S. persons may not receive services from the Government of Iran related to safe passage through the Strait of Hormuz. The FAQ identifies the Persian Gulf Strait Authority, or PGSA, as the designated entity behind those services. Any American shipowner, operator, or crew member who pays PGSA fees or follows PGSA routing instructions risks violating U.S. sanctions law.
Treasury has gone further, characterizing PGSA’s entire operation as maritime extortion. A Treasury press release describes PGSA as attempting to impose illegitimate tolls on vessels and compelling them to follow Iranian direction in exchange for safe passage. The framing is deliberate: Washington treats PGSA not as a legitimate maritime authority but as an arm of Iranian coercion, using the threat of seizure or harassment to extract compliance and revenue from commercial shipping.
On the operational side, the Maritime Administration issued advisory 2026-001A, addressing military operations and potential retaliatory strikes by Iranian forces across the strait, the Persian Gulf, the Gulf of Oman, and the Arabian Sea. That advisory instructs U.S.-flagged, U.S.-owned, or U.S.-crewed commercial vessels to maintain close contact with NAVCENT NCAGS, the Naval Cooperation and Guidance for Shipping program run by U.S. Naval Forces Central Command. The advisory also directs operators to review guidance from the United Kingdom Maritime Trade Operations center and the Joint Maritime Information Centre. Its language stops short of describing escort operations in detail, but the instruction to maintain close contact during active military operations implies coordination well beyond routine notices to mariners.
The economic math behind the chokepoint
Roughly 21 million barrels of crude oil and condensate pass through the Strait of Hormuz every day, according to the U.S. Energy Information Administration. That volume represents about a fifth of global petroleum consumption. The strait also handles a significant share of the world’s liquefied natural gas trade, with Qatari exports alone accounting for a substantial portion of global LNG supply.
Any sustained disruption would ripple through energy prices within days. War-risk insurance premiums for vessels transiting the Gulf have already climbed during previous periods of tension, and shipowners routinely pass those costs on through freight surcharges. For refiners in Asia, Europe, and the Americas, even the perception of elevated risk can push benchmark crude prices higher before a single barrel is actually lost. Reuters reporting has warned that consequences to global oil markets could be catastrophic if the strait were closed, an assessment grounded in the basic arithmetic of how much energy flows through this narrow channel and how few alternatives exist for rerouting it.
What the Navy is doing, and what remains unconfirmed
The U.S. Fifth Fleet, headquartered in Bahrain, maintains a persistent naval presence in the region through Combined Maritime Forces and its own carrier strike group rotations. During periods of heightened tension, the Navy has historically provided direct escort and guidance to commercial tankers. The most visible precedent was Operation Sentinel and the International Maritime Security Construct, established after a series of tanker attacks and seizures in 2019.
The specific claim that the Navy is now orchestrating AIS transponder shutdowns during guided transits has not appeared in any official advisory, press release, or congressional testimony available as of June 2026. AIS blackouts by commercial vessels in conflict-prone waters have been documented in other contexts, including the Red Sea during Houthi attacks, and the practice is consistent with operational security measures during periods of active threat. Defense and maritime industry sources have described the current arrangement as an evolution of earlier guidance programs, but the Pentagon has not commented publicly on the details.
The same evidentiary gap applies to Iran’s submarine deployments. Open-source defense references, including assessments from the International Institute for Strategic Studies and the Center for Strategic and International Studies, confirm Iran’s inventory of Ghadir-class boats and their suitability for shallow-water operations. But no U.S. government source in the current reporting cycle has specified how many submarines are deployed, where they are patrolling, or whether they have engaged in threatening behavior toward commercial traffic. The MARAD advisory references potential retaliatory strikes by Iranian forces without specifying submarine activity.
The questions Washington has not answered
Several gaps in the public record matter for anyone trying to assess the real level of risk in the strait.
First, PGSA toll collection data is almost nonexistent in open sources. Treasury describes the toll scheme as illegitimate and coercive, but neither OFAC nor the Treasury press release provides statistics on how many vessels have paid, how much revenue PGSA has collected, or how compliance rates have changed since sanctions were imposed. It is also unclear how many non-U.S. shipowners, who are not directly bound by OFAC rules, have continued to pay PGSA fees as a pragmatic hedge against detention.
Second, the role of allied navies remains underreported. The United Kingdom, France, and several Gulf states maintain naval forces in the region, and their posture toward PGSA and Iranian submarine activity would significantly affect the risk calculus for commercial operators. Whether allied navies are coordinating AIS protocols or providing their own guidance to merchant vessels has not been addressed in available U.S. government documents.
Third, China’s position is conspicuously absent from the discussion. China is the largest single buyer of Persian Gulf crude, and its tanker fleet transits the strait daily. Beijing’s willingness or refusal to comply with PGSA demands, and its diplomatic relationship with Tehran on maritime access, could shape the effectiveness of U.S. sanctions pressure more than any other single factor.
Where this standoff is heading
What can be confirmed as of June 2026 is this: U.S. authorities consider PGSA’s services off-limits to American persons, they view the toll regime as coercive, and they have instructed U.S.-linked vessels to stay in close contact with naval guidance channels while transiting a corridor where military operations are ongoing. The economic stakes are not hypothetical. A fifth of the world’s oil supply passes through a waterway narrow enough that a single grounded tanker or a well-placed mine could choke it.
What remains out of public view are the precise tactics being used on the water: how many tankers are going dark, how many submarines are lurking below the thermocline, and whether the combination of sanctions enforcement and naval coordination is actually breaking PGSA’s grip on the strait. Until more detailed operational data or declassified enforcement records surface, the Strait of Hormuz will remain both a physical chokepoint and an intelligence one, a place where the flow of oil is visible on the horizon but the struggle over who controls that flow is conducted largely beneath the surface.
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*This article was researched with the help of AI, with human editors creating the final content.
