The Strait of Hormuz: Iran’s Potential Countermeasure to US Hostility

Demolition charge near a U.S. vessel in the Strait of Hormuz (photo by Mass Communication Specialist 1st Class Joshua Lee Kelsey)

by Nader Entessar and Kaveh L. Afrasiabi

As the Trump administration ratchets up pressures on Iran—by re-imposing the sanctions removed under the terms of the Iran nuclear accord—Iran has responded diplomatically, politically, and militarily, combining the elements of both soft and hard power.

For instance, Iran’s navy has conducted a war game in the narrow waters of the Strait of Hormuz, where up to 30 percent of world oil exports travels each day. It test-fired a Fateh 10 radar-guided anti-ship missile over the Strait in what U.S. military officials called a clear “message to the U.S.” With missile batteries on the mainland of the strategically important strait as well as on Iran’s Persian Gulf islands, Iran’s message to the United States and its regional allies is, indeed, very clear.

This will not be a repeat of past clashes, when the United States sunk nearly half the Iranian naval force while incurring minimal costs. Iran now poses a much more formidable military challenge that ought to make the anti-Iran hawks in the Trump administration think twice about their current belligerent approach vis-à-vis the Islamic Republic.

Of course, in addition to its (mobile) missile arsenal, Iran counts on its submarine fleet, including three Russian-made Kilo-class diesel submarines, several frigates and corvettes, as well as several hundred missile boats designed to “swarm” the enemy as part of Iran’s strategy of asymmetrical warfare. An enhanced sea-mine capability and Russian S-300 batteries also provide Iran much better protection from potential air strikes.

Cycle of Escalation

If push comes to shove and the United States persists on its present dangerous course of maximum sanctions and an oil embargo, then Iran will likely retaliate in the Persian Gulf to raise the costs of U.S. bellicosity. It’s wishful thinking that a passive Iran would simply accept the harsh effects of U.S. sanctions on its economy without resorting to appropriate countermeasures. By waging economic warfare against Iran, the U.S. government has pushed Tehran’s back against the wall, thus inviting a level of tension in the Persian Gulf not seen since the 2003 invasion of Iraq.

As with the Iraq War fiasco, efforts are under way in the US to provide false public assurances about U.S. “preparations” to keep the Strait open in the event of an Iranian push to disrupt the flow of oil. But is the United States really prepared to assume the potential financial and military costs of such a gambit?

Iran’s missile threat is the principal reason the U.S. navy keeps a low profile in the Persian Gulf and prefers the relative safety of the Indian Ocean. The United States risks losing a number of its naval assets, including aircraft carriers, in a showdown with Iran. A decade ago, a British study predicted that the United States would lose several naval vessels in such a scenario, and Iran’s lethal power has much increased since then. Thus, if the United States engages in mine-clearing efforts as a countermeasure to Iran’s attempt to mine the shipping lanes in the Strait of Hormuz, then it is likely to set into motion an action-reaction dynamic in the theater of conflict. In other words, even a partial closure and an Iranian “harassment” strategy could culminate in a complete closure of the strait for an uncertain period, given the unpredictability of modern warfare.

Yet, a recent report by the Congressional Research Service (CRS) ignores such a possibility and paints a much less menacing picture of the Iran threat and its likely impact on global oil prices. Under the veneer of objectivity, this report also fails to mention that Trump’s withdrawal from the Iran accord is questionable from the standpoint of international law, given the UN Security Council’s binding resolution 2231 mandating the implementation of the accord by all member states. By reneging on its obligations and re-sanctioning Iran in clear violation of the UN Security Council’s directive, the Trump administration has effectively given Iran the right to complain of a casus belli, particularly since the attempted US oil embargo on Iran is tantamount to economic warfare and threatens the Middle Eastern country’s economic survival.

Should the United States succeed in its current bid to halt Iran’s oil exports, then Iran has just cause to hit back by seeking to deprive the United States of its oil imports from the Persian Gulf. Currently, the United States receives 10 percent of its oil imports from the Persian Gulf, nearly two million barrels per day. Under the principles of international legal theory, such Iranian countermeasures would fit the parameters of jus ad bellum, similar to Japan’s reaction after the U.S. imposition of an oil embargo in 1941, which FDR himself had earlier warned would “amount to war.” But, of course, the big difference between Japan then and Iran today is that Iran has not invaded any country and has been helping neighboring countries in their fights against international terrorism.

The International Context

To reiterate, the United States has no legal standing in its current economic aggression against Iran. The other world powers have uniformly expressed their “regret” and “disappointment” over the U.S. exit from the nuclear agreement when they ought to censure and condemn the United States at the Security Council just as they certainly would have had done if Iran unilaterally walked out of the deal. Iran’s ambassador to the UN, Gholamali Khoshroo, rightly raised this issue in a recent opinion column in The Guardian. International law dictates the uniform application of standards regardless of how powerful a country might be.

Fortunately, many nations including Turkey, China, and Russia have rejected the U.S. insistence on oil and trade sanctions on Iran. Europe, too, passed a new blocking regulation to protect their companies in Iran from U.S. secondary sanctions, which is tantamount to a repudiation of the White House, which refused European requests for waivers from the Iran oil sanctions. Compared to three months ago, when the Trump officials were openly demanding “zero oil imports” from Iran, today they are now realistically projecting the more modest target of reducing Iran’s exports by around one million barrels per day. But, even this figure might be wishful thinking, given that in the past Iran found creative ways to circumvent the oil embargo, such as transferring supplies between floating storage using barter trade. Today, Iranian traders have the option of trading Chinese yuan-denominated crude oil futures on the Shanghai International Energy Exchange.

Also, Iran can compensate for any losses in oil receipts due to US sanctions by escalating tensions in the Hormuz Strait to influence oil prices. Iran’s propensity to pursue this option depends on a number of inter-related factors, including the extent of sanction-related damage to Iran’s economy, the willingness of key importers such as India to comply with the US demand, and the potential failure of Europe to provide the deliverables because of U.S. pressure. Any sanguine prediction of future harmony in the Strait of Hormuz or, at worst, minimal disruptions well short of closure—reflected in the aforementioned CRS report—should be viewed with a good deal of skepticism. Such U.S. narratives underestimate the existential threat posed to Iran by hostile U.S. policy, which lacks legitimacy and broad support around the world, compared to international sanctions prior to the nuclear deal.

Contrary to a recent statement by Defense Secretary James Mattis, Iran has never in the past sought to completely close the Strait of Hormuz. But now thanks to its much-improved military capability and lack of distraction from other enemies, Iran might do so as a last resortCertainly, that would mean a major distraction for the US military, which is overstretched in dealing with the long-term strategic threats of Russia and China, not to mention North Korea. Chances are that North Korea, which furnished Iran with missiles in the past and which recently sent its foreign minister to Tehran, might do so again, perhaps in an oil-for-missile barter.

Iran’s threat to close the Strait of Hormuz represents a major U.S. vulnerability that Iran can exploit for the future. Its range of options include the selective harassment of international shipping, the slowing of oil shipping by conducting naval exercises, the interdiction of oil vessels, the sinking of vessels and thus hampering if not blocking oil transports, mining the waters, and outright closure in a worst-case scenario. That scenario may have been pushed to the background by the ongoing collective effort of other signatories to preserve the nuclear deal minus the United States. But it is premature to think that the United States will not somehow scuttle that effort to prevent a major international embarrassment.

There is, in other words, a direct correlation between the fate of the nuclear deal and the prospects for increased tensions and even the closure of the Strait of Hormuz. A much-needed U.S.-Iran dialogue, on the other hand, is the most appropriate way to neutralize this threat. Unfortunately, at the moment the necessary preconditions for this dialogue, including confidence-building measures, simply do not exist.

Nader Entessar and Kaveh Afrasiabi are political scientists specializing in Iran’s foreign affairs. Their latest works are: Iran Nuclear Accord and the Remaking of the Middle East (2018); Trump and Iran: Containment to Confrontation (forthcoming).

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  1. It is much simpler than all that. The Ayatollah regime cannot block the Straits of Hormuz, because that would block China and it would break international law. If that happens China will withdraw its support for the Ayatollah regime and the regime would collapse.

    I write this, but now read the derogatory comments to follow. These is my humble opinion. I written in much more detail in my own blogspot called Iran New Blog.

  2. And another factor to add is the ‘time’ which is against US position as well as continued hostility against other countries which is yielding the opposite. If US continue to isolate itself the Iran issue would be a small problem compared to the big picture of US bankruptcy due to reduced trust in USD. Everybody will increase its distance with a giant sinking ship. Cold waves of US could make Iran like that iceberg which sunk Titanic, the one that nobody thought to sink ever. Then, those who keep close would be those that would be drawn down by the giant waves of this upcoming whirlpool caused by sinking Titanic.

  3. Another excellent article by the authors thank you. Let us pray for peace not war!

  4. Ali: “It is much simpler than all that.”

    Well, no, sorry, you are being simplistic. If the Americans start to strangle the life out of Iran then “China’s continued support” will be neither here nor there.

    Ali: “If that happens China will withdraw its support for the Ayatollah regime and the regime would collapse”

    But if the Iranians do nothing then the regime will collapse, so in what way is your logic going to help them? It won’t. Their collapse is assured, “China’s support” notwithstanding.

    So they may as well go big, rather than simply whimpering as they are being strangled.

    You also seem not to be aware of the larger geopolitical aspect of this that will work towards China continuing to back Iran even if the Chinese suffer for it.

    Think about it: the USA pushes too hard, the Iranians block the Strait of Hormuz, the USA responds and then……. the USA fails dismally.

    The Iranians win, simply by not being defeated.

    The damage to US prestige would be huge.
    The ramifications beyond calculation.

    Who gains if the USA suffers such a self-inflicted and utterly unnecessary wound?
    Answer: China does.

    From the Chinese point of view that may well be worth the pain.

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