The United States and Iran have a history of strained relations and recent maritime developments have only heightened tensions. Since 2019, Iran has led a war against American and British-aligned shipping vessels in the Persian Gulf, ostensibly in response to the United Kingdom’s seizure of the Grace 1 in 2019. This poses a clear threat to global energy security and regional freedom of navigation, prompting renewed focus on the region by the US military.
Escalation and the brink of war
The Persian Gulf and by extension, the Strait of Hormuz, are some of the world's most important shipping lanes, especially for crude oil. The Gulf accounts for one-third of global crude oil reserves, with tankers transporting roughly 17 million barrels of oil through the Strait daily. This makes it one of the world’s most critical regions for global energy security.
Following the British seizure of the Iranian-flagged supertanker “Grace 1” in 2019, Iran launched a series of attacks targeting Western tankers in the Strait. These attacks saw Iran unlawfully seize numerous commercial tankers transiting through the Strait, violating the UN Convention on the Law of the Sea. Subsequently, over 100 confrontations unfolded between a Royal Navy frigate attempting to protect tankers and vessels belonging to the Islamic Revolutionary Guard Corps (IRGC). Furthermore, a significant US military build-up in the region to counter Iran culminated in the downing of an American drone, bringing the two countries to the brink of war.
Although cooler heads prevailed in 2019, Iranian attacks against tankers continued well into 2020. The seizure of a Hong Kong-flagged tanker, a tense confrontation in April between the US Navy and IRGC, and the US military build-up in the region in December rekindled fears of open conflict between the US and Iran. Fortunately, a change in leadership following the 2020 election helped avert any potential confrontation.
In 2021, a new US government led by President Biden saw the adoption of a new strategic approach. The Biden administration aimed to bring Iran back to the table for the Joint Comprehensive Plan of Action nuclear deal, shifting away from the militarised approach of the previous administration. Biden also sought to pivot US efforts towards addressing its biggest strategic threat, China, resulting in the deactivation of the forward-deployed US Marine Corps Crisis Response Force in the region.
New administration, new strategy
Russia’s invasion of Ukraine has put increasing pressure on global energy security and has underscored the importance of Persian Gulf oil. US and EU sanctions on Russian oil have begun to squeeze the global market resulting in rising energy prices and increased demand for Gulf oil. Saudi Arabia and the United Arab Emirates, both highly reliant on the Strait of Hormuz, are the only two countries capable of filling the gap made by Russian oil sanctions. Consequently, security in the Strait of Hormuz is regaining prominence as a US priority.
Iran's Grace 1 tanker was seized by the UK in 2019. Image: Jorge Guerrero via AFP.
The 2022 US National Security Strategy (NSS) made special mention of the volatile security status in the Strait and ensuring the safeguarding of freedom of navigation. Freedom of navigation is the right of all ships to transit international waters without being impeded, except in certain situations determined by international law. The NSS re-established the US commitment to preventing “foreign or regional powers to jeopardize freedom of navigation through the Middle East’s waterways, including the Strait of Hormuz”. As part of this commitment, the strategy outlined a two-fold approach to the region, combining both soft and hard power to ensure freedom of navigation and preserve regional security.
The US commitment to the strategy would be tested only a month after its release when Iran launched a drone strike against an oil tanker off the coast of Oman. A US response however wasn’t immediate and was mostly confined to international condemnation of Iran from the United States and Israel.
Now, halfway through 2023, the US has significantly increased its military presence in the region, a response to last year's drone attack and Iranian attempts to seize two commercial ships in July. This expanded commitment involves deploying thousands of marines and sailors aboard two US Navy ships, the USS Bataan and USS Carter Hall, which will support existing US Navy assets in the region, alongside the deployment of US Air Force jets in July.
Accompanying this renewed US presence is the proposal to deploy US forces aboard tankers transiting the Strait, a move not seen since WW2. It also highlights the region’s continued importance in US foreign policy and its continued commitment to defending freedom of navigation.
As expected, Iran did not take the US decision to deploy more forces lying down. It instead responded by equipping the IRGC’s naval forces with drones and long-range missiles that can “attack several targets simultaneously”. Despite Tehran’s thinly veiled threats, Washington remained steadfast in its commitments to the region. Iran’s attacks against tankers transiting the Strait threaten global energy security, necessitating a robust response from the US and its allies to ensure the uninterrupted flow of critical oil from the region.
To guarantee global energy security, it is essential Washington does not back down in the face of Iranian opposition. While the deployment of marines onto vessels may escalate tension, an increase of US naval and air assets in the region to work alongside Gulf partners will send the required message to Iran – its attacks will not be tolerated.
Dominic Graham is currently studying a degree in International Business at QUT and is interested in global energy security, power politics, and global security.