Before the war, about 15 million barrels of crude oil a day went through the Strait of Hormuz. In July, tankers using U.S. protected routes transported around five million barrels of oil daily out of the Persian Gulf, according to analysts.
Helping the tankers get out through the southern corridor increases the supply of crude to world markets and reduces the likelihood of oil prices spiking to the heights they reached earlier in the war. Gulf oil is also bypassing the strait by being pumped in greater volumes through Middle Eastern pipelines.
To try to protect vessels on the southern corridor, Central Command uses a range of weapons that can intercept Iranian drones and missiles. Ship operators say they register any planned trips through the strait with the U.S. military, and then report possible threats or attacks as they occur. The United States uses ships, helicopters and planes to launch weapons to intercept attacks. It has helped over 1,000 ships transit the strait, according to Central Command.
The U.S. tanker protection operation has drawn attacks by Iran. At least 15 ships taking the southern routes have been hit since the start of June, injuring 16 mariners and killing two, according to a New York Times analysis of data collected by the International Maritime Organization, a part of the United Nations. Another ship was struck this week while it was sailing close to Oman, killing a crew member, the United Kingdom Maritime Trade Operations, an entity administered by Britain’s Royal Navy, said on Tuesday.
A small number of shipping operators have been willing to use the Oman route. One of those is Dynacom, a Greek company. Two of its tankers were hit on July 19, one of which was abandoned, according to the International Maritime Organization. Dynacom did not respond to requests for comment.
The United Arab Emirates’ government-owned oil giant, the Abu Dhabi National Oil Company, or ADNOC, is making considerable efforts to move oil on the southern route.
Its vessels have also been frequently struck. ADNOC said last week that 18 of its vessels had been attacked in the war, resulting in one fatality and 20 injuries to crew members.
Many large shipping companies have chosen to stay away from the strait until there is a lasting cease-fire, and traffic through the strait remains far below what it was before the war.
“It’s one of the surprising successes,” said Michelle Wiese Bockmann, a shipping analyst at Windward, a maritime analysis firm. “They have been extraordinarily effective in keeping that southern corridor operating, despite the attacks.”
Ships that navigated the strait with the assistance of Central Command, the U.S. military unit running the operation, typically turn off their transponders to avoid detection by Iran. That makes it harder for firms that track vessels to get a full picture of traffic in the strait.
Given that Iran has regularly struck ships using the southern route, the U.S. protection has not been impregnable. But Capt. Tim Hawkins, a spokesman for Central Command, said: “It doesn’t mean the defense is ineffective. As you can see in the grand scheme, more ships are moving through than before.”
But the U.S. effort, which Iran opposes, has come at a cost.
The U.S. military is deploying significant resources to get a limited amount of oil through the strait — something it did not have to do before the war, when tankers sailed freely through the waterway.
The Iranian military retains the ability to escalate its attacks on all shipping in the area, as well as on oil and gas facilities in Gulf countries. And Iran is demanding permanent control over ship traffic in the strait, something it did not have before the war.