The United States steadily continues to tighten the screws on Iran, prompting an upswing in Iranian rhetoric implying that closing the Strait of Hormuz is on the table as a military option in response to U.S. actions. While Iran’s naval capabilities are ill-equipped for a total closure, these threats from high places may reflect a less drastic but still dangerous escalation in the Strait.
The Strait of Hormuz is one of the most important trade routes in the world. Around 40 percent of the world’s oil exports pass through it, totaling about 17 million barrels per day. Accordingly, any threats to the Strait of Hormuz, whether real or imagined, may significantly affect market movement, considering that all of the world’s oil or natural gas importers—including the United States—depend on secure shipping traffic moving through the Strait.
While concerns about the Strait have existed for decades, the issue flared up recently up after a phone call between U.S. President Trump and King Salman bin Abdulaziz. During the call, Trump asked Saudi Arabia to increase oil production to cover the needs of the European Union and other states currently relying on Iranian oil exports. The Kingdom readily acquiesced, increasing its rate of crude oil exports by nearly 330,000 barrels a day this month and exceeding the average Saudi oil export rate of 10 million barrels per day. This increased output reflects a rejection of the agreed-upon quotas in the policies of Organization of the Petroleum Exporting Countries (OPEC).
Increased Saudi oil production represents yet another economic stranglehold on Iran, coinciding with the difficult economic conditions that Iran has had to face, given the renewal of sanctions. The Iranian government has also dealt with significant domestic pressure, as popular protests in throughout Iran against the country’s economic situation have sprung up recently.
In response, Iranian President Hassan Rouhani indicated during his visit to Switzerland that his country would take actions to prevent neighboring countries from exporting their oil through the Strait of Hormuz. Mohammad Ali Jafari, Commander of the Iranian Revolutionary Guard Corps (IRGC), issued similar statements to this effect, claiming “either all can use the Strait of Hormuz or no one.”
Infeasibility of Closure
On the one hand, it is highly unlikely that Iran can completely seize control over the Strait of Hormuz. This is especially the case considering that it has previously moved most of its large warships to the Caspian Sea and Indian Ocean regions. Its naval forces in the Strait of Hormuz only consist of a network of conventional surface ships and small submarines, mostly dating back to the 1960s and 1970s. And although the navy is effective at asymmetrical raiding in the Strait, they do not represent an organized naval force that follows recognized military conventions.
The United States’ large military presence in the Gulf regions is a stark challenge to any Iranian attempts to threaten navigation through the Strait of Hormuz. The United States has reinforced its military presence in the Gulf since 2011 in coordination with both the United Kingdom and France in order to ensure that its Gulf allies can freely transport oil through the Strait.
Therefore, it is safe to say that Iran, even if it succeeded in blocking the Strait for a brief period, would not last against a direct U.S. naval assault. Reflecting this reality, the Iranian MP Heshmatollah Falahatpisheh has recently acknowledged that Iran cannot close the Strait of Hormuz and that Rouhani’s latest statements are nothing more than for media consumption. Given the conflicting messages from Rouhani and the IRGC, the effectiveness of this type of threat raises questions of the Iranian military’s abilities to escalate pressures on the Gulf without triggering a U.S. military response.
On the other hand, Iran’s naval provocations in the Strait of Hormuz, while perhaps not enough to close the Strait entirely, have had several security repercussions for Gulf and international interests. In disrupting the maritime flow in the Strait of Hormuz, Iran still has several options for continuing a flow of goods in and out of the country. Iraq, Turkey, Pakistan, and even Qatar have become increasing important land trade routes in recent times, especially as these countries did not sign the agreement imposing international sanctions on Iran.
Iran continues to impose its control over Iraq's energy sector as well as over several strategically important oil fields along the border strip. As of late, recent protests in Southern Iraq have aborted Iraqi attempts to stop paying for Iranian energy. Turkey is no less important than Iraq in terms of Iran's regional economic support, as it has played a significant role in rescuing Iran’s political regime from several political crises it has faced since 2017. As for Pakistan, it is the main artery connecting Iran’s oil to Eastern and Southeast Asian countries.
Given these overland economic outlets, even temporary disruptions in the Strait driven by Iran’s IRGC Navy would prove economically damaging to other Gulf countries over and above what Iran would suffer. Whereas the Iranian military’s naval forces are responsible for the Indian Ocean and Caspian Sea regions, the Iranian regime has given responsibility for securing the interests of the Arab Gulf region over to the IRGC Navy. Perhaps this is to complement the strategy of the IRGC’s ground force in other conflicts in the Middle East, as it the main arm of Iran’s regional strategy for its western neighbors. The IRGC Navy is particularly successful in its ability to apply its asymmetrical war tactics to a “hit-and-run” naval strategy, allowing it to rapidly attack and raid shipping vessels and oil facilities without prior warning.
Were direct military confrontation to break out in the Strait of Hormuz, Iran’s ability to launch concentrated anti-ship missile attacks with small naval units would give it a significant advantage over attacking enemy vessels, especially were efforts concentrated on individual targets over blanket closure. Iran is also the only nation in the Arab Gulf region that possesses a submarine force, which it developed after the Iraq-Iran War by receiving three second-class attack submarines from Russia.
Iran has sought to gain and impose decentralized control over the Strait of Hormuz region through purchasing a large number of small boats and arming them with missiles, small cruisers and submarines, anti-ship ballistic missiles, a swarm of UAVs harnessed with bombs for suicide attacks on enemy vessels, as well as naval helicopters.
Were Iranian obstruction policy escalated to match its current leadership’s rhetoric, the Strait could still be compromised if not closed entirely. Even partial disruption could frustrate Saudi efforts to increase international oil supply and American interests in providing countries who are currently reliant on Iranian output with alternatives. Given these concerns, those U.S. and European naval forces stationed in the Strait should be especially wary of efforts to disrupt the flow of oil, even if this does not exhibit itself as an outright attempt to close the Strait.