The United States has increased its forces in the Middle East, even as President Trump has promised to end the war against Iran soon. In recent days, more than 5,000 marines, paratroopers and special forces have arrived in the region, raising the possibility of a ground invasion.
Mr Trump threatened last week that he would invade Kharg Island, Iran’s main oil export hub, and “destroy” its facilities if Iran did not allow shipping through the Strait of Hormuz to resume. Iran has essentially shut it down since the attack by the United States and Israel a month ago.
To reach Kharg Island, US amphibious forces – which experts say would likely be part of some ground operation – would have to cover about 500 miles across the Persian Gulf. “It would be very risky,” said Mark F. Cancian, a retired Marine Corps colonel and senior adviser at the Center for Strategic and International Studies. “So I think opening the strait might be the first.”
U.S. officials say the president is also considering whether to seize islands in and near the strait to open the waterway, which in normal times carries a large share of the world’s oil and gas.
With several islands as well as military outposts along the coastline, Iran can quickly cover the narrow shipping lanes with drones, antiship missiles and fast-attack speedboats.
Given Iran’s firepower, the United States would have to capture the entire group of islands to try to open the strait, said Farzin Nadimi, a senior fellow at the Washington Institute, which includes Qeshm, Larak, Abu Musa and Tunb Islands. “They need to take them all,” he said.
The United States has deployed 2,000 paratroopers, as well as special operations forces, to the region. If they land on the islands, they could destroy tunnel networks and underground missile bases that are “inaccessible even to bunker buster bombs,” Dr. Nadimi said.
Commanders would need to decide whether to destroy the facilities and withdraw, or hold the islands long enough to help secure the strait. They may also offer benefits to the United States in negotiations with Iran.
But a long-term stay would require heavily equipped Marines and air defenses to protect the coastline from Iranian drones, missiles and rockets. It would be a “high-risk, high-casualty undertaking,” Dr. Nadimi said.
A ground operation alone will not guarantee that ship traffic will return to the strait in meaningful numbers.
“You have to reassure sailors, you have to reassure shipping companies and insurance companies that it is safe enough for sailing,” said Andreas Craig, a senior lecturer at the School of Security Studies at King’s College London.
Even with the capture of one or multiple islands in or near the strait, Kharg Island would still have significant strategic importance for Mr Trump.
Ninety percent of Iranian oil is exported from the island, and massive US strikes there in March did not stop oil shipments. Satellite images showed that tankers continued to arrive at the island’s export terminals in the days after the attack.
Experts say that the American occupation of Kharg Island will put great pressure on the Iranian economy. “This is the weak link in the regime’s oil export infrastructure,” said Behnam Ben Taleblu, senior director of the Iran program at the Foundation for Defense of Democracies.
But any attempt to land US troops on the island would be dangerous due to the mountainous terrain and military presence. The flammable oil accumulating there poses a danger in itself.
Experts have warned that Iran could adopt a scorched-earth policy, destroying oil installations on the island rather than allowing US forces to occupy them. And for the Trump administration, there are political risks.
If the Marines took an island but failed to force an Iranian surrender, any eventual withdrawal might look like a defeat. And if they tried to take over any of the islands, Iran would likely try to turn it into a conflict.
Mr. Craig said, “What they want is to cause maximum harm to Americans, because this creates images that will change public opinion in the United States.”
