Following U.S. strikes on its nuclear facilities, the Iranian parliament was quick to vote in favour of closing the globally vital Strait of Hormuz. As things stand at the time of writing, a tenuous ceasefire has been struck between Israel and Iran, with an increasingly impatient President Trump acting as mediator. Whether this arrangement holds into the future remains to be seen, but the swift posturing clearly demonstrated something more permanent about the Iranian perspective. Iran’s control over the Strait of Hormuz is seen as a powerful ace in the hole that can be used in the interest of the regime.
But is it? To what degree can Iran feasibly take advantage of it? Given recent developments, I thought it fitting to run through the worst-case scenario: the country decides on a ”hard” shutdown of the strait, or what might be called the “military option”. In this hypothetical, Iran’s full resources are marshalled to forcibly stop any ship from passing through the strait.
An obvious path is to make use of the Iranian navy for this purpose, but there are notable limitations. Even though the naval forces as a whole are of a respectable size and suitable to a number of coastal defense roles, they would simply not have the reach or punch to permanently blockade the strait. It’s nearly guaranteed that a war would immediately be declared, in which the U.S. and Gulf state navies are likely participants, as well as possibly the aforementioned Asian states.
Direct naval engagements with overwhelming opposing forces would therefore likely be kept to a minimum, in favour of so-called “asymmetric warfare” tactics. Swarms of smaller boats, anti-ship missiles and drone systems could be used to try and overwhelm opposing forces. Indeed, recent years have shown the Iranians focusing on exactly this type of kit. The naval drone carrier Shahid Bahman Bagheri was recently put into service for instance, and many of Iran’s vessels are equipped with anti-ship missile platforms. As for how these swarm tactics are likely to end up looking, Iran has helpfully provided demonstrations already. Small boats have been spotted swarming and attacking a prop aircraft carrier, very similar to the USS Nimitz, during Iranian military exercises near the strait.
As for missiles, Iran hosts one of the largest and most varied stockpiles in the world. Tehran has invested heavily in the development of cruise and ballistic systems, as well as in the platforms to launch them. ”Missile cites” – large underground complexes equipped with transport corridors and launch silos – have appeared all over the country. On top of this there are signs that the military is exploring the concept of ”missile farms” — buried launch tubes in scattered locations, that emerge from the ground and launch when needed. In an all-out conflict where the goal for Iran is to block the strait, one probable outcome is the state using up this missile arsenal, by striking at enemy ships frequently and from unexpected places.
A longer-term naval strategy would be to make the sea lanes themselves untraversable. According to some estimates Iran has thousands of sea mines stockpiled. By seeding the ocean floor with them, it could tie up its opponents for weeks. One important duty for the Iranian navy in the initial phase would likely be to provide cover for such minelaying operations, performed by both surface and submarine vessels. Minelaying wouldn’t be exclusive to naval operators, either. Returning to missiles shortly, the Fajr-5 Multiple Launch Rocket System (MLRS), which can fire several medium-range missiles from the back of a truck, now appears to be equipped with unconventional minelaying warheads.
If any of this took place, international trade through the Gulf would of course be hampered. There would be impassable physical barriers for tanker ships, but some financial ones as well. Large ships like oil tankers are extremely expensive, and regularly insured. Of course, insurance firms demand a premium for their services, which may be increased in the event of war breaking out in a relevant region. There is some debate around just how much heightened premiums would affect Gulf shipping. During the Iran-Iraq ”Tanker War” for example, shipping never stopped entirely, despite frequent attacks on tankers in the Gulf and soaring insurance rates.
The duration of a crisis like this would depend entirely on the speed of opposing forces’ minesweeping, as well as on the removal of other threats like targeted missile strikes. Considerable resources and a firm commitment would certainly be required to safeguard the waterway, as well as a high degree of air superiority throughout the region. For a country like the United States, maintaining the required level of presence in the Persian Gulf is absolutely possible — it’s been done in the past. However, it risks drawing attention away from other important areas, notably China and Taiwan.
From the Chinese perspective, the U.S. Navy being tied down in another Middle Eastern conflict would be an eminently desirable outcome, if it wasn’t for one gaping weakness: China needs the strait open, too. U.S. Secretary of State Marco Rubio recently called on the Chinese to convince Iran not to block the corridor, due to the country’s reliance on Persian Gulf oil imports. During a press conference the day after, Chinese Foreign Ministry spokesperson Guo Jiakun mentioned that the area is important for international trade, but no real position on Iran’s posturing was provided. As it happens, China is indeed reliant on those oil imports. Most of the crude oil and liquefied natural gas (LNG) shipments passing through the Strait of Hormuz end up in Asian states like China, India, South Korea and Japan. Out of these, China represents the lion’s share of the import volume.
What this means is that non-NATO U.S. allies like South Korea and Japan would certainly be affected by a closure of the strait – according to one research group’s analysis, they are actually the most reliant of the bunch – but China is not impervious to the damage it would cause. There is a real Chinese interest in keeping the strait open for business. A major winner in a worst-case scenario might ironically be the Russian Federation, which has been competing with Iran for crude oil exports to China, ever since the withdrawal of European buyers in 2022. A shutdown of the strait would remove this competition and increase Chinese demands for Russian oil.
Which finally brings us to Iran itself. Despite the parliament’s decision, Iran is reliant on the Strait of Hormuz as well. Natural resource exports amount to a large share of government funds and, amidst several sanctions and limited international investment, sources of dependable income are scarce. There is also internal strife that opponents could seek to exploit, should an all-out war erupt in the region. A large contingent of Iranian Arabs live in the west, notably in the oil-rich Khuzestan region, whose separatist movements have in the past been courted by Saudi Arabia. Another example is the Baloch people, living in the southeastern parts of the country, who have historically had a tense relationship with the government. Ethnic divisions could become a thorn in the side of Tehran, in an event where an opponent actively uses them against the regime.
All in all, there are definitely military pathways for Iran, if it really wanted to halt traffic through the strait and harm the global economy. A fifth of the world’s oil consumption flows through it, and the effects of turning that stream off are not to be scoffed at. However, there is an argument to be made that Iran could be harmed more grievously than the opponents it seeks to cripple. A large chunk of state income would disappear, erstwhile allies would suffer, and a litany of powerful militaries would be given just cause for a large-scale intervention. A ”middle of the road” strategy could presumably be to threaten action only against ships of a certain origin. However, this approach both precludes mining the strait and it blunts the impact that an encompassing blockade would create.
So far, the Strait of Hormuz remains open. Unless the situation is truly dire and Tehran sees no alternative, I believe it’s likely to stay that way.
[Photo by Mohammad Sadegh Heydari, CC BY 4.0, via Wikimedia Commons]
The views expressed in this article are those of the author and do not necessarily reflect TGP’s editorial stance.
Robert Bergkvist is a Swedish Master’s graduate of International Relations. He also holds a Bachelor’s degree in Political Science. He resides in Poland, working as an IT specialist.
