On 12 March, UK Maritime Trade Operations (UKMTO) reported that Source Blessing, a container ship chartered to Hapag-Lloyd and sublet to its alliance partner Maersk, was operating on Maersk’s M04 shuttle service in the Gulf.
A small fire was reported on board, though a damage assessment could not be carried out in the dark. The vessel is currently anchored in the northwestern part of the Gulf, having been en route to the Omani port of Sohar before the outbreak of the war.
The incident marked the 14th attack on vessels sailing in the Arabian Gulf, some of which had attempted to transit the Strait of Hormuz. The following day, US Defence Secretary Pete Hegseth said that “the only thing prohibiting transit in the strait right now is Iran shooting at shipping. It is open to transit should Iran not do that.”
In December last year, the Iranian Navy staged the Shahid Mohammad Nazeri naval drills, followed in January by the exercise Deterrence 1404 and Smart Control drills in February. These manoeuvres converged on a single strategic objective: the closure of the Strait of Hormuz.
They were under close US scrutiny. Dan Caine, a seasoned military strategist and chairman of the US Joint chiefs-of-staff, fully recognised the gravity of the situation. According to the Wall Street Journal, “Caine told the president in several briefings that US officials had long believed Iran might attempt to block the critical shipping lane using naval mines, drones and missiles if conflict erupted. Trump reportedly acknowledged the risk but decided to move forward with the military campaign, telling advisers he believed Tehran would likely capitulate before taking such a step, and that the US military would be capable of reopening the waterway if necessary.”
The Iranian Tasnim news quoted Alireza Tangsiri, commander of the naval forces of the Islamic Revolutionary Guard Corps (IRGC), as saying in a statement that claims by the United States about destroying Iran’s navy or providing safe escort for oil tankers were false. The Strait of Hormuz has not been militarily blocked and is merely under control, it said.
“The Strait of Hormuz is open. It is only closed to the tankers and ships belonging to our enemies, to those who are attacking us and their allies. Others are free to pass.”
This raises the important question of why Caine finds the situation so difficult to manage, despite the near-total destruction of the Iranian naval fleet in recent days?
The answer lies in Iran’s calculated use of Gulf topography to shape a strategy centred on its so‑called Strategic Gatekeeper Islands. The unoccupied islands of Qeshm and Hormuz command the main shipping lanes, while the occupied islands of Greater and Lesser Tunbs and Abu Musa provide positions for coastal missile batteries and radar systems directly in the path of approaching naval groups.
From these vantage points, Tehran has layered three lines of coastal defence: Raad and Noor missiles with ranges of 120 to 200 km that can span the Strait of Hormuz and effectively shut it to surface traffic; Qader and Ghadir extended‑range variants reaching up to 300 km and capable of striking targets deep into the Gulf of Oman or central Persian Gulf; and Khalij Fars anti‑ship ballistic missiles designed to hit moving vessels such as carrier strike groups.
Beyond conventional missile deployments, Iran has also embraced an unconventional “Smart Control” doctrine. This integrates swarms of more than a thousand loitering munitions, Shahed and Arash types launched from coastal silos, with thousands of fast-attack craft armed with missiles and employing swarm tactics to overwhelm Aegis‑class defences. Naval mines add a further layer, serving as a low‑cost but highly effective tool for physically blocking shipping routes.
US Navy destroyers and aircraft carriers are primarily designed for operations in the open ocean and not the shallow waters of the Gulf. This was the principal reason for the deployment of US Coast Guard cutters in the region prior to combat operations, most of them from the Sentinel class.
These vessels are armed only with multi‑calibre machine guns and lack the robust defensive systems needed to withstand sustained Iranian strikes. By contrast, destroyers are capable of providing escort duties, yet the shallow waters and their proximity to shore make them far more vulnerable to attack.
US Central Command (CENTCOM) Chief Brad Cooper, himself a naval officer, is acutely aware of this critical situation.
According to the Wall Street Journal, “US Secretary of Defence Pete Hegseth has approved a request from US Central Command for an element of an Amphibious Ready Group and attached Marine Expeditionary Unit… An Amphibious Ready Group (ARG) typically includes an assault ship, two transport docks, and a support vessel that carries an embarked Marine Expeditionary Unit (MEU) of at least 2,200 Marines.”
The units now slated to deploy to the Middle East include the 31st Marine Expeditionary Unit, comprising roughly 2,200 marines and sailors equipped with light armoured vehicles. Most of the force will be embarked aboard the amphibious assault ship USS Tripoli, supported by the cruiser USS Robert Smalls and the destroyer USS Rafael Peralta.
In addition, the 31st MEU brings significant airpower to the theatre, with the ability to operate F‑35B fighters alongside AH‑1Z Viper, UH‑1Y Venom, and CH‑53E Super Stallion helicopters.
There is little doubt that the deployment of this force marks a turning point in Operation Epic Fury against Iran. It is expected to succeed in sweeping assaults against any island or area it seeks to seize near the Strait of Hormuz, with Iranian forces unable to withstand the overwhelming firepower from air and sea accompanying the marines.
But the entire operation hinges on the unit’s ability to endure Iran’s relentless war of attrition and waves of drone and ballistic missile strikes continuing day and night for days on end.
While an Iranian ground counterattack against the US marines is unlikely given American air superiority, the persistent use of artillery, drones, and varied munitions will ensure constant pressure not only on the expeditionary force but also on shipping transiting the Strait of Hormuz.
The USS Tripoli will require two weeks to reach its new destination from Japan, a deployment that will be preceded by sustained preparatory fire on the Iranian islands. In the meantime, the Islamic Revolutionary Guard Corps (IRGC) is reinforcing its positions, deploying additional drone and missile launch platforms in the Zagros Mountains and establishing new observation posts.
The coming weeks are certain to yield hard lessons from the ongoing military operations, where the absence of diplomacy leaves both sides relying solely on force to impose their will.
Published in cooperation between the Egyptian Center for Strategic Studies, Al-Ahram Weekly, and the English-language portal Ahram Online
