How Risky Is Iran's Move to Double Down on Pressure via Hormuz?

War reignited after Iran attacked at least three commercial vessels in the Strait of Hormuz last Tuesday, as claimed by United States officials and international maritime authorities.

The attacks targeted a Saudi Arabian oil tanker and a Qatari-owned liquefied natural gas (LNG) carrier. The incident prompted the United States to revoke a temporary waiver on Iranian oil export sanctions.

The waiver was one of the major concessions in the memorandum of understanding (MoU) agreed by the United States and Iran last month. That deal allowed Tehran to resume oil exports after its tanker fleet became trapped by a US Navy blockade.

In retaliation, the United States Central Command (CENTCOM) said last Wednesday it had struck more than 80 targets in Iran, including air defence systems, radars, and more than 60 fast boats belonging to the Islamic Revolutionary Guard Corps (IRGC) that have long been used to harass shipping.

The US military said on Thursday (9 July) it launched a new wave of attacks on around 90 targets in Iran.

CENTCOM said the operation aimed to “impose a very heavy cost for targeting and attacking commercial vessels crewed by innocent civilians in international shipping lanes.”

Iran then responded by launching fresh missile attacks against several Gulf states. Air raid sirens and explosions were reported in Bahrain and Kuwait. Further attacks were also reported on Thursday.

Responding to the escalation, maritime security firm MARISKS warned that the tit-for-tat actions “mark the return of direct military confrontation.”

Ahead of the NATO summit in Turkey, US President Donald Trump said the MoU with Iran was now “over”. He added: “Dealing with them [Tehran] is just a waste of time.”

Meanwhile, China and Qatar called for de-escalation of the conflict. German Defence Minister Boris Pistorius also urged Tehran to stop provocations against Washington and end attacks on commercial vessels.

Why did Iran attack ships in Hormuz again?

Iran is trying to maintain its grip on the Strait of Hormuz, the sea lane through which roughly one-fifth of the world’s oil and gas exports from the Gulf region passed before the war, bound for destinations worldwide.

Iran effectively closed the strait after US and Israeli air strikes killed a number of senior officials, including Supreme Leader Ayatollah Ali Khamenei, on 28 February. Iran subsequently attacked around a dozen ships trapped in the strait before last month’s fragile ceasefire agreement was reached.

In the days leading up to Tuesday’s attacks, peace negotiations had shown almost no progress on various outstanding issues, including the long-term lifting of US sanctions and Iran’s nuclear ambitions.

Iran has repeatedly used Hormuz as a bargaining chip in negotiations whenever diplomatic channels reached an impasse. In addition, Tehran has launched attacks on Gulf states such as Saudi Arabia, the United Arab Emirates, and Qatar.

For Tehran, attacking major oil-producing countries that are also key US allies is a way to pressure Washington and spread instability so that the Middle East region also feels the impact of the war.

How much leverage does Tehran have?

Repeated US and Israeli attacks have crippled much of Iran’s military strength. But rather than engaging in conventional warfare, Tehran has waged asymmetric warfare by targeting strategic US facilities in the Gulf and blockading the world’s oil routes.

Although Iran does not legally own the Strait of Hormuz, it controls the northern coastline, a number of strategic islands, and coastal positions that allow the IRGC to monitor and threaten passing vessels.

Iran uses fast attack craft, coastal missiles, mines, and drones to attack tankers. These tactics have succeeded in disrupting global energy supplies without engaging in full-scale naval battles.

According to various reports, Iran has also begun charging up to US$2 million, or around Rp36 billion, per ship to guarantee safe passage through Hormuz. Maritime experts have condemned the move as illegal.

Iran insists ships must use shipping lanes it designates in its northern territorial waters. The US, by contrast, supports the use of routes closer to Omani waters.

However, Tehran’s coercive power is not unlimited. The White House responded by imposing a naval blockade at Hormuz preventing Iranian ships from exporting oil, cutting off one of Iran’s most important sources of revenue.

Until now, Iran has continued exporting oil in violation of US sanctions, mainly to China, at below-market prices.

Tehran uses a shadow fleet of tankers that frequently change flags, operate without tracking systems, and transfer cargo between ships to evade detection.

Yet without the sanctions waiver and with the possibility of a US Navy blockade being reimposed, Iran now faces serious risks to an economy already in tatters.

According to the Washington-based think tank Foundation for Defense of Democracies, the war has caused economic losses totalling US$144 billion for Iran, plus billions of dollars more from oil revenue lost during the blockade.

The rial has also plunged to its lowest level in history, at around 1.7 million rial per US dollar, while inflation has soared past 88 per cent.

Iran rejects intimidation

In its latest statement, MARISKS said the revocation of sanctions waivers for Iran “erodes the political foundation” of the peace deal while “reducing the incentive to continue exercising restraint.”

The maritime intelligence firm warned that “the likelihood of further escalation has increased significantly.”

Although Trump said negotiations would probably continue, he described Iran as being led by “sick people” and made clear he no longer wished to deal with the regime.

A US official quoted by Bloomberg urged Tehran to act responsibly if it wishes to enjoy the benefits offered by the joint memorandum of understanding.

Nevertheless, Iran has maintained a defiant stance. Parliament Speaker Mohammad Bagher Qalibaf wrote on X: “The era of intimidation and extortion has ended. That approach will not produce results. We will not surrender.”

As oil prices jumped 5 per cent following the latest escalation, a number of analysts warned that further American attacks would most likely not change Tehran’s strategy.

“On the contrary, such a move risks pushing both sides further away from a negotiated outcome that … apparently remains the preferred option for both Washington and Tehran,” wrote Dennis Citrinowicz, a visiting fellow at the Atlantic Council think tank, on X.