By: Andy Wong Ming JunUSS Dwight D. Eisenhower. Photo from US Navy via APThe war with Iran has exposed uncomfortable truths about the limits of American naval power, with implications that extend far beyond the Persian Gulf to the broader foundations of US global dominance and deterrence. What was intended as a decisive exercise of force has instead highlighted structural weaknesses in fleet composition, doctrine, and strategic reach for the US Navy.Together, these limitations raise questions about the durability of Pax Americana and the credibility of US commitments in other theatres, including the defense of Taiwan.When the United States launched Operation Epic Fury at the end of February, it did so following the largest American naval buildup in the Middle East since the Iraq War. Over two months, more than a third of the US Navy’s operational battlefleet was concentrated in the Eastern Mediterranean and Arabian Sea, anchored by two carrier strike groups centered around the USS Gerald R. Ford and USS Abraham Lincoln. This deployment, combined with a sustained air and missile campaign that effectively destroyed the Iranian Navy within days, was meant to demonstrate overwhelming American superiority and compel regime change in Tehran.Yet the results have fallen short of expectations. Unlike the earlier Caribbean deployment that contributed to the capture of Nicolás Maduro and made limited progress toward regime change in Venezuela, Iran has proven far more resilient. Even after the deaths of Ayatollah Khamenei and much of the senior leadership of the Islamic Revolutionary Guard Corps (IRGC) in the opening days of the conflict, the Iranian state has remained intact and operationally effective even if in limited fashion to retaliate with missile and unmanned drone strikes by air or sea.Three interrelated lessons emerge from this conflict, each pointing to deeper vulnerabilities within the US Navy.First, the centrality of aircraft carriers and the Arleigh-Burke class destroyers, long the two centerpieces of American naval strategy and surface battlefleet composition, has come under scrutiny. While carrier strike groups remain potent symbols of US power projection, capable of delivering sustained strikes and asserting control over vast maritime spaces, their ability not just in operating within constrained and heavily contested littoral environments, but even attempting to approach them by sea appears increasingly limited.In the case of Hormuz, the US Navy has demonstrated neither the willingness nor the practical ability to challenge Iranian control and access denial directly. The risks posed by overlapping threat vectors of antiship missiles, explosive drones and underwater mines make contested entry and escort operations into the constrained littoral environs of the Strait of Hormuz and Persian Gulf prohibitively dangerous for large warships.At the same time, the US Navy’s shipborne defense systems are primarily missile-based and optimized for intercepting large, high-end aerial threats like enemy warplanes or ballistic missiles. They are entirely unsuited for point or area defense against small, low-end aerial drone swarms or kamikaze drone boats. Efforts to enhance point-defense capabilities for US warships with newly-upgraded remote gun turrets are underway, but these remain in early stages and are not meant to be permanently equipped as standard fleetwide.Second, the naval war has exposed a structural imbalance in the composition of the US fleet. Decades of investment and doctrinal thinking have prioritized large, capital-intensive platforms such as aircraft carriers and destroyers for blue water combat against peer adversaries, often at the expense of smaller, more numerous vessels suited to less intense escorting duties and littoral combat. The retirement of the Cold-War era Oliver Hazard Perry-class frigates in 2015 and the failures in subsequent replacement programs such as the Littoral Combat Ship (LCS) and Constellation-class frigate have left a gap in precisely the sort of cheap, lower-end ships needed for escort duties, minesweeping, and littoral operations.This capability shortfall has had immediate consequences. The absence of sufficient minesweepers exacerbated by the recent withdrawal of aging Avenger-class vessels built in the 1980s has limited the Navy’s ability to clear safe corridors. Meanwhile, LCS vessels equipped with minesweeping modular kits were intended to fill this niche, but recent reports indicate that the minesweeping kits are qualitatively inadequate. In any case, such LCS minesweepers are not even currently present in the theater in meaningful numbers to make a difference, with two of the three deployed for Operation Epic Fury currently withdrawn thousands of miles away to Singapore.Without a balanced force structure, the US Navy faces a dilemma: risk its high-end Arleigh-Burke class destroyers which form the bulk of its surface battlefleet to contest asymmetric high-threat environments like the Strait of Hormuz, or concede operational space to weaker but more adaptable adversaries such as the IRGC. With oil price at over US$100 a barrel of Brent Crude, every day that the Strait remains closed despite five Arleigh-Burke class destroyers nearby in the Arabian Sea is yet another dent in the navy’s capability to deter and defeat threats to freedom of navigation in international waters.Peacetime freedom of navigation cruises through the Taiwan Strait and South China Sea in the past made it easy to maintain the illusion of Pax Americana. The failure to reopen the Strait of Hormuz by force against an adversary with no navy to speak of has now shattered said illusion for good.Third, the strain on overall force availability reveals the true scope of American naval reach and power projection. The redeployment of the amphibious assault ship USS Tripoli and its Marine contingent from the Pacific to the Middle East illustrates a broader pattern of resource reallocation. With only a handful of Amphibious Ready Groups (ARG) available and fewer still fully operational, the navy has struggled to meet simultaneous commitments across regions. US Indo-Pacific Command (INDOPACOM) has longstanding issues with amphibious vessel availability due to maintenance backlogs and ARGs only being deployed transitionally through them on their way to Central Command (CENTCOM) in the Middle East.This increasingly entrenched “robbing Peter to pay Paul” dynamic carries significant strategic implications. The Asia-Pacific, where US naval and amphibious presence is central to deterring Chinese action against Taiwan, has already experienced gaps in amphibious and carrier coverage over the past two decades. The last time an ARG finished a full deployment and was not asset-stripped from the Asia-Pacific to other regions was in late 2022 and early 2023. The almost-reflexive constant diversion of forces meant for the Indo-Pacific Command to Central Command further weakens that posture, even as China continues to conduct large-scale exercises simulating blockades or an invasion of Taiwan.Taken together, these developments challenge longstanding assumptions about American naval dominance. The US remains qualitatively unmatched for high-intensity combat and long-range power projecting strike operations, as demonstrated by the destruction of Iranian conventional naval forces and land targets by US carrier aviation and ship-launched cruise missiles. However, such superiority does not automatically translate into control of contested maritime chokepoints, freedom of navigation for global trade, or success in coercive “gunboat” diplomacy.Instead, the current conflict suggests that US naval power functions increasingly as a glass cannon. Immensely powerful, but constrained by vulnerability, cost, and limited numbers. In environments where adversaries can implement an anti-area, access denial strategy in a cost-effective manner with drones, mines, and coastal antiship missile systems, the US Navy simply does not have the risk tolerance to take damage or lose any of its warships to force contested waters.For Pax Americana, the implications are profound. The US through its Navy has long underwritten the post-1991 global order, ensuring freedom of navigation and providing credible defense support for its allies. If the US Navy cannot have either the will nor the means to reopen by force the Strait of Hormuz against a regional power like Iran with no navy to speak of, questions will inevitably arise about its ability to do so elsewhere.Nowhere is this more consequential than in Northeast Asia. The credibility of US commitments to Taiwan depends not only on formal alliances and political will, but on the ability to deploy and sustain forces in the face of Chinese efforts to challenge for command of the Western Pacific. Beijing, Taipei, Seoul, and Tokyo will doubtlessly be studying the naval aspect of the ongoing US-Iran war closely. Only one will take positive encouragement from it.Andy Wong Ming Jun specializes in defense commentary for Asia Sentinel