US President Donald Trump, in a bid to squeeze Tehran economically, this week announced a blockade of maritime traffic leaving and arriving at Iranian ports.
He is attempting to press the Iranian regime into reopening the Strait of Hormuz, a vital passage for the shipment of Middle Eastern oil transiting the Gulf, and end its nuclear programme in negotiations led by Vice-President JD Vance.
Talks faltered over the weekend, but the US President has said that they could resume later this week.
Trump told Fox Business in an interview today that he thought the war in Iran - which the US and Israel started - could be over “very soon”.
He expected fuel prices to fall to pre-war levels by the US Midterm elections in November “on the assumption” that the US is able to stop Iran obtaining a nuclear weapon.
“When that’s settled, gas prices are going to go down tremendously,” he said.
Iran escalated threats to choke off international trade, with military commander Major-General Ali Abdollahi saying Iran would block imports and exports from the Gulf, Gulf of Oman and Red Sea in response to the US blockade.
“Iran will take powerful action to defend its national sovereignty and interests,” he said in comments reported by Iran’s semi-official Tasnim news agency.
More than a dozen US Navy warships are positioned in the Gulf of Oman and the Arabian Sea to enforce the US blockade, confronting vessels as they exit the Strait of Hormuz.
US military officials said on social media that none had made it through the blockade during its first 48 hours, and that nine ships complied with directives to turn around and go back to an Iranian port or coastal area.
Oil tanker traffic through the route has now been choked for six weeks since US and Israel airstrikes on Iran began on February 28, causing retaliatory strikes and a global fuel crisis.
A radio transmission posted online by US military officials appeared to show a US service member announcing the blockade to ships in the region.
“Do not attempt to breach the blockade,” it says. “Vessels will be boarded for interdiction and seizure transiting to or from an Iranian port. Turn around, or prepared to be boarded.”
The arrival of additional American warships will put even greater pressure on Iran and provide Admiral Brad Cooper, head of US Central Command, and other senior military leaders with more options should negotiations fail, said James Foggo, a retired Navy admiral and dean at the Centre for Maritime Strategy in Northern Virginia.
“The more tools you have got in your kit, the more diversity of options that you have,” Foggo said, calling the injection of additional forces “a reserve capacity, in the event that things go south”.
White House press secretary Karoline Leavitt, asked about the expanding military presence, said in a statement that Trump “has wisely kept all options on the table in the event that the Iranians will not forgo their nuclear ambitions and make a deal that is acceptable to the United States”.
Trump, Vance and US negotiators have “made the US redlines very clear,” she said, predicting that Iran’s “desperation for a deal will only increase” with the blockade in effect.
The Pentagon and US Central Command, which oversees military operations in the region, declined to comment.
The arrival of the additional forces will provide commanders with three aircraft carriers in the region, each with dozens of fighter jets.
The USS Abraham Lincoln has been in the Middle East since January, while the USS Gerald R. Ford arrived in the eastern Mediterranean Sea in February, extending a marathon deployment that included time last year in Europe and involvement in operations off Venezuela at the beginning of this year.
The USS George H.W. Bush was close to the Cape of Good Hope, near South Africa, yesterday and expected to make an unusual hook around the bottom of the continent on its way to the Middle East, two officials familiar with the matter said. The path to the region was first reported by USNI News.
The three-ship Boxer Amphibious Ready Group last week departed from Hawaii and is now a couple of weeks from the Middle East, US officials said. The embarked 11th Marine Expeditionary Unit includes an infantry battalion of more than 800 personnel, plus helicopters and naval landing craft. A similar unit, the 31st Marine Expeditionary Unit, arrived in the Middle East from Okinawa, Japan, late in March.
A former senior defence official said that US forces involved in Trump’s blockade are probably on the lookout for ships suspected of supporting Iran.
Armed boarding teams from the Navy SEALs, Marine Corps or Coast Guard are trained to seize vessels, whether their crews co-operate with US forces or not, the official said.
Shipboarding can be an exceedingly dangerous mission, though. Any US personnel who may have to do so face the risk that embarked mariners will fight back or that Iranian forces will target the boarding teams with drones or speedboats, the former senior defence official said.
Trump has appeared to acknowledge the risks to US personnel participating in the blockade, warning in a social media post that Iran’s Navy already is “laying at the bottom of the sea, completely obliterated”, and any smaller vessels that approach US personnel could face a similar fate.
“Warning: If any of these ships come anywhere close to our BLOCKADE, they will be immediately ELIMINATED, using the same system of kill that we use against the drug dealers on boats at Sea,” Trump wrote, referring to the Pentagon’s campaign of strikes in Latin American waters. “It is quick and brutal.”
Any ships that are seized are likely to be sent to another location to be held in quarantine, the former senior official said.
Foggo, the retired admiral, said he sees promise in the blockade, given how much Iran’s economy is underpinned by the export of oil through the Strait of Hormuz.
“It’s a lot of pressure, and if it’s sustained over a period of time, it’s going to really hurt the Iranian economy,” he said.
“At the same time, you have to admit, gas prices are going to continue to go up. So, that is a problem for us and our policymakers, as well, because people are not happy about it.”
As the blockade continues, military officials are planning for another potential escalation: US ground operations on Iranian soil, two US officials said.
Administration officials have discussed everything from launching a complex Special Operations mission to extract Iranian nuclear material, to landing Marines on coastal areas and islands to protect the strait, to seizing Kharg Island, an Iranian export facility in the Gulf, officials have said.
Enforcing an extended blockade will be a “tall order” for US forces, but any of those ground operations would be significantly riskier, said Mick Mulroy, a retired Marine and CIA officer who served in the Pentagon during the first Trump Administration.
Mulroy said he hopes that the Administration and Iran can find an agreement that is acceptable to both sides. If, for example, they can agree to a deal that pauses the Iranian nuclear programme for 10 or 20 years, that must be balanced against the challenges Marines and soldiers could face while deployed on Iranian soil.
“It’s not going to be without consequences,” he said of such a mission. “There will likely be casualties.”
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