President Hassan Rouhani’s apparent threat to block the Strait of Hormuz in retaliation for looming US sanctions on Iranian oil exports has made headlines around the world. The strait is a vital route through which one-third of sea-borne oil flows to the Arabian Sea. In 2016, it amounted to 18.5 million barrels per day — the highest volume for any maritime chokepoint in the world. While Rouhani never explicitly referred to the waterway by name, his language seems to be an implicit warning to the West — and especially the United States. During his tour of Switzerland and Austria in early July, Rouhani said, “The Americans say they want to reduce Iranian oil exports to zero. … It shows they have not thought about its consequences.” He then added, “It would be meaningless that Iran cannot export its oil while others in the region can. Do this if you can and see the consequences.”
This is not the first time that Iran has made such a threat.
During the 1980-88 Iran-Iraq War, senior Iranian officials repeatedly issued warnings about closing the strait. In 1983, founder of the Islamic Republic and Supreme Leader Ayatollah Ruhollah Khomeini stated, "I warn the regional states as well as countries which make use of oil … that Iran, exercising its utmost power, will oppose this aggression and is determined to block the Strait of Hormuz, thus obstructing the passage of even a single drop of petroleum from there, should such an aggression be actualized." Late former President Akbar Hashemi Rafsanjani said in 1983, “We will block the Strait of Hormuz when we cannot export oil.” The following year, Rafsanjani elaborated, “We never said we will simply close the Strait of Hormuz, nor do we wish to have it closed, because if it were to be closed it would harm us too and we will incur losses. Therefore, we have always emphasized that we will close the Strait of Hormuz if the Persian Gulf becomes unusable for us. And if the Persian Gulf becomes unusable for us, we will make the Persian Gulf unusable for others also."
More recently, amid the tightening of sanctions on Iran during the presidency of Mahmoud Ahmadinejad, Vice President Mohammad Reza Rahimi said in December 2011, “If they impose sanctions on Iran’s oil exports, then not one drop of oil will flow from the Strait of Hormuz.” Iran never carried out that threat, even though its oil was sanctioned by not only the United States but also the European Union.
The Islamic Republic has been loath to close the strait for several reasons. First and foremost, Iran relies on the waterway for the conduct of a major portion of both its oil and its non-oil trade with the world. Moreover, such an action would invite likely harsh reactions from friendly states who rely on the free flow of oil, including China and India, alienating Tehran when it needs its partners the most. Lastly, it would in all likelihood trigger a strong military response from the United States and its regional allies, who would aggressively move to seize control of the waterway.
Thus, what distinguishes the most recent Iranian warning is the individual who has voiced it. The constant threats by the Ahmadinejad administration were usually not taken seriously in the West or inside Iran. On the other hand, Rouhani has shown himself to be a man of action. Upon taking office, the moderate president has also worked toward establishing constructive engagement with the West, culminating in the Joint Comprehensive Plan of Action (JCPOA).
Mindful of the history of Iranian threats to close the strait and the domestic context of Rouhani’s recent remarks, it seems as though the aim of the president’s warning was primarily to mollify hard-liners at home. As the achievements of the 2015 nuclear deal continue to unravel, Rouhani seems to be moving closer to his archrivals to at the very least reduce the domestic pressures on his administration.
It's notable that Rouhani’s threat has been welcomed by military figures in Iran. Maj. Gen. Qasem Soleimani, the commander of the elite Quds Force, wrote in an open letter addressed to the president on July 4, "Your valuable statement that said there will be no guarantees for oil exports from this region unless the Islamic Republic of Iran [can] also export its oil was a source of pride." Soleimani added, “This is the Dr. Rouhani who we knew and know and who must be."
The following day, Islamic Revolutionary Guard Corps commander Maj. Gen. Mohammad Ali Jafari praised what he described as the administration’s “revolutionary” stance against US threats and said, “Definitely, through the implementation of the latest positions adopted by the country's executive officials, under contingencies the enemies can be made to understand … the meaning of 'either all or none’ can use the Strait of Hormuz.”
Tension has been growing between the Rouhani administration and its opponents in recent months. Hard-liners have gone as far as reminding the president of the fate of Abolhassan Banisadr, Iran’s first president following the 1979 Islamic Revolution who was impeached in 1981 and fled the country. Against this backdrop, many observers believe Rouhani’s threat was made with the intention of getting closer to this domestic audience. Heshmatollah Falahatpisheh, the new head of parliament’s national security and foreign policy commission, has said, “President Rouhani did not mean that he will close the Strait of Hormuz, because this is governed by international law that must be complied with.”
Hard-line media outlets warmly welcomed the president’s implicit threat. Javan's July 5 front page featured an image of Soleimani and Rouhani shaking hands with the caption “Meeting in the strait.” On the same day, fellow hard-line newspaper Vatan-e-Emrooz praised Rouhani’s remarks in a piece headlined “Decoding oil threats.”
The reality is that under US President Donald Trump, Rouhani has been pushed harder than ever toward Iran’s hard-line camp. Given the rising tensions between Iran and the United States, Rouhani appears to be seeing the JCPOA — the realization of which was his main campaign pledge in the 2013 presidential elections — as a lost cause, especially since the European signatories to the nuclear deal have not been able to fill the gap created by the US withdrawal from the accord. Thus, given that the promised economic dividends of the JCPOA have evaporated, Rouhani has seen his support base disappear too. At the same time, increasing US threats have amplified the domestic pressures on Rouhani, including criticism from hard-liners. It now seems that the president has adapted to this new atmosphere by moving closer to the hard-liners to avoid becoming a lame duck. A continuation of this trend, in the shadow of Europe’s failure to take serious steps to preserve the diplomatic achievements of the JCPOA, will likely lead to the weakening of both Reformist and conservative voices in Iran, while paving the way for the empowerment of hard-liners.