Could the Islamic Republic of Iran close the Strait of Hormuz, described as the “greatest economic choke point in the world” where nearly 20 per cent of crude oil traded globally passes, thereby cutting off Persian Gulf energy exports vital to the functioning of the global economy? While it has long been considered highly probable that Iran could close the strait if attacked by the United States or Israel, could it close the strait over economic sanctions which are proving highly effective in cutting off Iranian energy exports? This idea has more recently been given serious consideration thanks to statements by senior Iranian officials and a proposed law by Iran’s parliament. While there has been much media speculation about Iran’s intentions and capabilities to close the strait, a recent statement by IRGC Navy deputy commander Admiral Ali-Reza Tangsiri sheds light on this important question. According to Tangsiri:
“Our enemies frequently claim that the Islamic Republic wants to close the Strait of Hormuz and we say that sane reasoning dictates that as long as Iran is using the Strait of Hormuz it will not close it…but this does not mean that we will put aside the strait…Our presence in the strait exists and under the circumstance that we cannot pass through the strait we shall not allow others to pass through.”
This statement, along with other considerations, suggest Iran’s approach to the Strait of Hormuz, in a scenario in which there is no state of open military hostilities in the Persian Gulf but economic sanctions persist, straddles the space between a military response and inaction. On the one hand many rightly consider Iran’s military capabilities in terms of closing the strait to be limited. However, for the Islamic Republic not to factor the strait into its overall strategy would be to ignore a potentially powerful strategic leverage against the US. On the other hand, closing the strait (for example by mining key passageways) when there are no ongoing military hostilities could give the US a strong pretext to strike Iran, potentially crippling Iranian military forces and other infrastructure. Furthermore it would inhibit Iran’s own ability to export oil, worsening its economic situation, and hurt relations with key Iranian allies such as China who rely on oil exported through the Strait of Hormuz. Finally, closing the strait would accelerate the diversion of Arab Gulf energy traffic away from the strait to alternative routes such as pipelines, decreasing the strait’s importance. It thus appears highly unlikely that Iran would close the strait in the absence of a military conflict with the US.
Under these circumstances Iran appears to have taken a strategy that uses the strait as a strategic leverage against the US and international community, but does not block the strait. It calls this strategy “intelligent control”. One of the most likely ways Iran could carry out this strategy is by imposing a rigorous inspection regime on all non-friendly shipping passing through the Strait of Hormuz. This could have a number of implications for the global maritime trade in energy. First, such an inspection regime would significantly slow down traffic through the strait, creating problems in the delivery of energy resources to their destinations on time. Second, it could increase the risk of shipping through the strait (for example by increasing the likelihood of a collision between vessels), leading to higher maritime insurance premiums. Finally, imposing such an inspection regime could increase tensions with the US and its allies, creating greater volatility in the energy market. All of these could lead to higher global energy prices, potentially allowing Iran to compensate for revenues lost from lower oil export quantities as a result of economic sanctions. It would also give Iran a way of signalling its displeasure without engaging in hostile military action against shipping in the Gulf.
It is unclear whether Iran has the military and technical capability to impose such an inspection regime, if it would be considered valid under international law, and the price it would pay in terms of upsetting the international community and inviting military and nonmilitary responses. However, if economic sanctions continue to take a toll on the Iranian economy and possibly even intensify, such an option may appear more and more tempting for Iran to force the US and American allies back to the negotiating table.