US naval manoeuvres near Iran

Sunday 15 March 2026

The latest reports of United States naval forces and Marine expeditionary units moving towards the Persian Gulf represent a familiar but consequential phase in the strategic choreography of American power projection. Amphibious ships, warships and several thousand Marines are reportedly being deployed as tensions escalate with Iran, particularly around the Strait of Hormuz, one of the world’s most critical maritime chokepoints. 

These manoeuvres, occurring amidst an already intense air and missile campaign against Iranian military assets, raise two questions that go to the heart of contemporary American strategy in the Middle East: what precisely are these deployments intended to accomplish, and is the additional firepower likely to achieve Washington’s strategic objectives?

The nature of the deployment itself offers the first clues. Reports indicate that a Marine Expeditionary Unit of roughly 2,200 Marines, supported by an amphibious assault ship such as the USS Tripoli and additional naval vessels, is being redirected towards the region.    Such formations are designed not merely for naval patrol but for rapid amphibious operations. They typically combine aviation assets including F-35B fighter aircraft with landing forces capable of conducting raids, securing coastal infrastructure or evacuating civilians.

In other words the deployment provides the United States with a spectrum of operational options rather than a single predetermined course of action.

The immediate strategic purpose of these movements appears to be connected to the Strait of Hormuz. Iran has reportedly targeted commercial shipping and threatened to halt oil exports passing through the narrow waterway, a channel through which roughly a fifth to a quarter of global energy shipments travel. The disruption has already caused shipping delays and volatility in global energy markets.

In this context American naval deployments serve several distinct but overlapping strategic purposes.

The first is deterrence. Moving large amphibious ships and carrier-capable aviation into the theatre signals to Tehran that escalation will incur overwhelming military costs. Force posture shifts of this sort have historically been used by Washington to influence Iranian decision-making by demonstrating both capability and political resolve. 

The second purpose is the protection of global maritime commerce. US officials have discussed the possibility of naval escort missions for tankers passing through the Strait of Hormuz, potentially organised as an international coalition operation once military conditions allow. Such escort missions are reminiscent of the “Tanker War” phase of the Iran-Iraq conflict in the 1980s, when US naval forces protected shipping in the Gulf against Iranian attacks.

The third purpose is operational flexibility. Amphibious Marine units provide the capability for limited ground operations along Iran’s coastline or on strategically important islands controlling maritime routes. Their presence also allows the United States to conduct rescue operations, secure damaged infrastructure or respond quickly to Iranian attempts to mine shipping lanes.

Finally, the deployment reinforces ongoing military operations against Iranian capabilities. Since the beginning of the current conflict phase US and allied strikes have reportedly hit thousands of Iranian military targets and destroyed a significant number of naval vessels.    Additional naval forces increase the capacity to sustain these operations while protecting American ships and bases from retaliation.

Yet the question remains whether these deployments can achieve Washington’s broader strategic objectives.

If the objective is limited, such as reopening maritime traffic in the Strait of Hormuz and deterring Iranian naval harassment, the additional firepower may well succeed. American naval power remains unmatched in the region. Carrier aircraft, cruise missiles and advanced surveillance systems give the United States overwhelming capacity to destroy surface vessels, mine-laying craft and coastal missile batteries. Indeed US strikes have already reportedly eliminated numerous Iranian naval assets during the current conflict. 

However success becomes far less certain if the objective extends beyond maritime security into political transformation within Iran.

Iran’s defensive strategy has long been built upon asymmetric warfare. Rather than confronting the United States fleet in conventional battle, Tehran relies upon swarms of small boats, land-based missiles, drones and naval mines deployed from its long coastline along the Gulf. These methods are comparatively cheap and extremely difficult to suppress entirely. Even a handful of mines or missile strikes can disrupt shipping and drive insurance costs sky-high, achieving strategic effect without decisive battlefield victory.

Moreover the geography of the Gulf favours the defender. The Strait of Hormuz at its narrowest is only about twenty-one nautical miles wide, placing shipping routes well within range of Iranian shore-based weapons. Naval superiority does not eliminate this vulnerability.

There is also the political dimension. Military deployments intended as deterrence can sometimes have the opposite effect, encouraging adversaries to escalate in order to demonstrate resilience. Iran’s leadership has historically responded to external pressure with nationalist mobilisation, portraying confrontation with the United States as a defence of sovereignty.

The presence of Marine amphibious forces also introduces a different set of risks. While they offer operational flexibility they simultaneously raise speculation about possible ground operations. Even limited landings could escalate the conflict dramatically, drawing the United States into the kind of protracted regional war that Washington has sought to avoid since the experience of Iraq.

Thus the deployment represents both strength and uncertainty.

In purely military terms the United States retains overwhelming superiority. Her navy can strike targets hundreds of kilometres inland, destroy surface fleets and impose air superiority across much of the Gulf. The introduction of additional Marines and amphibious ships expands that capacity further.

But strategic outcomes rarely depend upon firepower alone. Iran’s asymmetric tactics, geographical advantages and political resilience mean that even a vastly stronger military may struggle to achieve decisive results.

The most plausible outcome of the current manoeuvres is therefore not the defeat of Iran but the stabilisation of a volatile maritime theatre. The United States seeks to reopen the Strait of Hormuz, reassure allies and prevent Iran from translating harassment tactics into sustained disruption of global energy flows.

Whether that goal can be achieved without widening the war remains the central strategic question now confronting Washington.