Michael Rubin, a former Pentagon official, predicted a retaliatory strike would take place to ensure the safety of Red Sea shipping.
“This is no longer a war against Iran,” he said. “This is rapidly becoming a war about energy flows and the freedom of navigation ... every time there has been a challenge to freedom of navigation, it’s led to military action.”
Alan Eyre, a diplomat who negotiated the Iran nuclear deal under Barack Obama, also said the Houthi attack would probably lead to US strikes on Yemen.
But a senior Israel Defence Forces (IDF) official told Kan News it had been prepared for a Houthi attack since the war broke out on February 28 with joint US and Israeli strikes against Iran.
“The Houthis are a distraction. We are not confused, and we continue to attack Iran with all our might,” the individual said. “We will choose when and how to hit the Houthis, according to our considerations. They will pay the price.”
The Houthis said the attack was in response to continued strikes by the US and Israel on infrastructure across Iran, Lebanon, Iraq and the Palestinian territories.
Until now, the terror group had refrained from joining the Gulf conflict, adding that strikes would continue until “the aggression” ended.
The missiles have prompted fears that the Houthis could shut down the Bab el-Mandeb Strait, a busy Red Sea chokepoint that has become an alternative route for ships since Iran’s closure of the Strait of Hormuz caused oil prices to surge.
The closure has prompted speculation of a US ground invasion, with thousands of US marines arriving in the Middle East on Saturday onboard the USS Tripoli.
US Central Command (Centcom) confirmed on Saturday (local time) that the amphibious assault ship, carrying 2500 US marines, had arrived in the Middle East, with transport and strike fighter aircraft.
The warship is equipped to transport F-35 fighter jets and Osprey aircraft, used for troop and cargo transport.
There is widespread speculation that the 31st Marine Expeditionary Unit (MEU) could be used in an amphibious invasion of targets such as Kharg Island, Iran’s major oil terminal, to pile pressure on the regime to end its chokehold on the Strait of Hormuz.
The 11th Marine Expeditionary Unit, aboard the USS Boxer, is also expected to arrive in the Middle East in the coming days.
Marco Rubio, the US Secretary of State, said the US could meet its objectives “without any ground troops” but said the presence of US marines gave US President Donald Trump “maximum optionality” for “multiple contingencies”.
Former diplomats have told the Telegraph that the marines will be an important means of exerting pressure on Iran as Trump claims to be holding peace talks, so that the Iranians do not run down the clock.
But now, with the Red Sea also potentially under threat, the US may need to reconsider its resources to ensure safe passage through both shipping lanes.
The Houthis had previously blocked the Bab el-Mandeb Strait, known as the “Gate of Tears”, by attacking ships using drones and missiles.
The group attacked more than 100 merchant vessels with missiles and drones, sinking two vessels between November 2023 and January 2025, in response to the war in Gaza. The attacks forced ships to take the much longer route around Africa and defence analysts said the group had entered the war on Tehran’s orders.
The missile launch on Saturday (local time) came after Iranian military officials had promised to create insecurity in the Red Sea.
The Bab el-Mandeb Strait connects to the Mediterranean through the Suez Canal and is one of the few alternative shipping routes to the Strait of Hormuz. Around a 10th of the world’s oil flows through it.
The strait separates Yemen on the Arabian Peninsula from Djibouti and Eritrea on the Horn of Africa and is one of the busiest shipping lanes in the world, acting as a key link between Europe and Asia.
Brigadier Yahya Saree, a military spokesman for the Houthis, claimed responsibility for the missile launch towards Israel on the rebels’ Al-Masirah satellite television channel.
Saree said on Friday (local time) that the group’s “fingers are on the trigger for direct military intervention” if any new alliances joined the war against Iran or the Red Sea was used for “hostile operations” against Tehran.
Ari Heistein, a research fellow at the Jerusalem Institute for Strategy and Security, said it was possible the Houthis had joined because of “external pressure” from Tehran.
“The Houthis were initially reluctant to rush to Iran’s defence due to their own domestic considerations,” he said. “Joining the fight risked further undermining their legitimacy among the Yemeni public and adding additional strain to an already decimated economy.
“Yet they joined a month into the conflict, driven either by growing external pressure, including repeated threats in Iranian media to activate the group, or an assessment that they could manage the domestic fallout. Despite their initial caution, they may yet escalate further if they do not meet significant pushback.”
Last April, the US hit more than 800 targets in Yemen, killing hundreds of fighters and destroying air defence systems and weapons factories. The US said this degraded the effectiveness of Houthi attacks, cutting missile launches by 69% and drone attacks by more than half.
‘Menace’ in the Red Sea
Heistein said that the group had been weakened by previous strikes on their operations but had been using the time since to rebuild.
“So far, they appear to be focusing primarily on Israel because their Red Sea campaign taught them that alienating many powerful countries simultaneously can be extremely costly.
“Their role as an international menace in the Red Sea helped solidify anti-Houthi coalitions and lent retaliatory actions legitimacy on the world stage, a dynamic very different from their earlier confrontation with Saudi Arabia. Kinetic strikes on the group’s economic assets, sweeping sanctions and decapitation strikes on key leadership all took a painful toll.
“After nearly half a year of quiet, they have presumably used that time to rebuild before the current round of fighting. This is the unfortunate reality of any pause or ceasefire with a jihadist group like the Houthis: it is exploited to rest and re-arm. Even so, they are unlikely to want to expend all of their limited resources in defence of Iran.”
Philip Ingram, a defence analyst and former colonel in British military intelligence, said the Houthis were effectively an “extension” of Iran’s Islamic Revolutionary Guard Corps.
“They don’t do anything under their own initiative and they may have been short of or tried to protect longer-range weapons that they’ve got,” Ingram said.
“They were happy to attack ships and Israel when American aircraft weren’t around but they will have seen the US come in recently and held back.
“Now the Iranians have probably asked them to do this to split the focus within the war. I think the next logical step would be for them to start attacking shipping again.”
The Houthis have held Sana’a, Yemen’s capital, since 2014 and may have stayed on the sidelines until now as they have held a ceasefire for years with Saudi Arabia, which launched a war against the group on behalf of Yemen’s exiled Government in 2015.
Ingram said that it was possible that Saudi Arabia wanted to enter the war, with Iranian drones and missiles attacking US bases on its soil, and that a Houthi blockade of the Red Sea could anger Riyadh.
“Saudi has been making a number of noises about joining the war and if that happens we’ve got an escalation that is one level above,” he said.
“As soon as Saudi starts to directly attack Iran then we are at another level of this historical religious civil war and the whole of the Middle East could erupt because of it.
“I think the Saudis want to get involved and I think the Americans are probably asking them just to take a step back at the minute. Do the Americans need them? Probably not. I don’t think the Saudis would defy the Americans by joining without their consent.”
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