President of Iran Hassan Rouhani threatened to close the Strait of Hormuz in response to potential sanctions that could be levied upon Iranian oil exports, threats which were echoed by the Islamic Revolutionary Guard Corps (IRGC). President Donald Trump has given countries until November 4, 2018, to stop importing petroleum from Iran. This wide-scale ban is part of a new campaign of confrontation and pressure against the Islamic Republic. This demand comes on the heels of the U.S. departure from the Joint Comprehensive Plan of Action (JCPOA), also known as the Iran nuclear deal, which was signed in 2015.
During negotiations, the JCPOA was marketed as the only option for curtailing Iran’s nuclear program short of war. Supporters of the deal routinely cited an increased risk of war in their arguments against exiting the deal and Rouhani’s statement, on the surface, appears to confirm such concerns. But how seriously should these threats be taken?
We’ve Been Here Before
Iran threatening to close the Strait of Hormuz is nothing new. In fact, as recently as 2012, the Obama administration had its own confrontation with Iran over the latter’s nuclear program. Iran threatened to close the Strait and carried out military exercises in the area, drawing a major United States, British, and French deployment in response. But a year later, both sides resorted to negotiations that led to the JCPOA.
In 2008, citing fears of a U.S. or Israeli attack, the commander of the IRGC, Mohammad Ali Jafari, threatened to close the Strait of Hormuz in retaliation. During the 1980–88 Iran-Iraq War, both sides targeted one another’s shipping as part of a total war effort, raising fears that Iran might attempt to make the Strait of Hormuz unpassable. Iran used mines as part of its strategy, eliciting an operation to safeguard Kuwaiti shipping, codenamed Operation Earnest Will. Beginning in summer 1987, it lasted over a year-and-a-half and involved increasingly direct combat between the United States and Iran, culminating in Operation Praying Mantis in spring 1988. In the one-day air/naval battle, the United States scored a decisive victory, with Iran losing several warships during the exchange, while inflicting no losses in return.
Apart from the events that took place from 1987–88, none of these incidents resulted in open warfare. This is nothing short of remarkable, given the unrelenting level of hostility exhibited on both sides since the November 4, 1979, seizure of the U.S. embassy in Tehran. While the lack of actual fighting can be attributed to restraint and professional crisis management skills on the part of the United States, it can also be attributed to the fact that Iranian behavior and rhetoric regarding the Strait primarily serves as a means of crisis-management (albeit a dangerous one) and a political purpose.
Threatening Closure Is More Useful than Executing One