What to know about Yemen's Houthi rebels as the US steps up attacks on Iran-backed group

DUBAI, United Arab Emirates (AP) — The United States under President Donald Trump has launched a new campaign of intense airstrikes targeting Yemen's Houthi rebels.

This weekend's strikes killed at least 53 people, including children, and wounded others. The campaign is likely to continue, part of a wider pressure campaign by Trump now targeting the Houthis' main benefactor, Iran, as well.

Here's what to know about the U.S. strikes and what could happen next:

Why did the U.S. launch the new airstrikes?

The Houthi rebels attacked over 100 merchant vessels with missiles and drones, sinking two vessels and killing four sailors, from November 2023 until January this year. Their leadership described the attacks as aiming to end the Israeli war against Hamas in the Gaza Strip. The campaign also greatly raised the Houthis' profile in the wider Arab world and tamped down on public criticism against their human rights abuses and crackdowns on dissent and aid workers.

Trump, writing on his social media platform Truth Social, said his administration targeted the Houthis over their “unrelenting campaign of piracy, violence and terrorism.” He noted the disruption Houthi attacks have caused through the Red Sea and Gulf of Aden, key waterways for energy and cargo shipments between Asia and Europe through Egypt's Suez Canal.

“We will use overwhelming lethal force until we have achieved our objective,” Trump said.

Didn't the U.S. already target the Houthis with airstrikes?

Under former President Joe Biden, the U.S. and the United Kingdom began a series of airstrikes against the Houthis starting in January 2024. A December report by The International Institute for Strategic Studies said the U.S. and its partners struck the Houthis over 260 times up to that point.

U.S. military officials during that period acknowledged having a far-wider target list for possible strikes. While the Biden administration didn't go too far into explaining its targeting, analysts believe officials largely were trying to avoid civilian casualties and not rekindle Yemen's stalemated war, which pits the Houthis and their allies against the country's exiled government and their local and international allies, like Saudi Arabia and the United Arab Emirates.

The Trump administration, however, appears willing to go after more targets, based on the weekend's strikes and public remarks made by officials.

“We’re doing the entire world a favor by getting rid of these guys and their ability to strike global shipping,” U.S. Secretary of State Marco Rubio told CBS News' “Face The Nation” on Sunday. “That’s the mission here, and it will continue until that’s carried out.”

Rubio added: “Some of the key people involved in those missile launches are no longer with us, and I can tell you that some of the facilities that they used are no longer existing, and that will continue.”

Israel also launched its own airstrikes on Houthi-held sites, including the port city of Hodeida, over the rebels' missile and drone attacks targeting Israel.

What could the new U.S. strikes mean for the wider Mideast?

In two words: More attacks.

The Houthis said last week they'll again target “Israeli” ships traveling through Mideast waterways like the Gulf of Aden and the Red Sea, because of Israel's blocking of aid to the Gaza Strip. No rebel attack targeting commercial shipping has been reported as of Monday morning.

However, the new U.S. campaign likely could inspire Houthi attacks at sea or on land beyond American warships. The rebels previously targeted oil infrastructure in Saudi Arabia and the UAE, two countries deeply involved in Yemen's war since 2015.

“Although the U.S. has been striking at Houthi targets for over a year, the scope and scale of this new campaign, including the targeting of senior Houthi figures, marks a significant escalation in the conflict,” analysts at the Eurasia Group said Monday.

Gulf Arab countries "will distance themselves from ongoing hostilities but now face threats to their major oil infrastructure. The Houthis will want to hit President Donald Trump where it hurts, oil prices.”

Meanwhile, the Houthis likely will expand their possible targets for ship attacks, meaning shippers will continue to stay out of the region, said Jakob P. Larsen, the head of maritime security for BIMCO, the largest international association representing shipowners.

Where are the Iranians in all of this?

Iran long has armed the Houthis, who are members of Islam’s minority Shiite Zaydi sect, which ruled Yemen for 1,000 years until 1962. Tehran routinely denies arming the rebels, despite physical evidence, numerous seizures and experts tying the weapons back to Iran. That's likely because Tehran wants to avoid sanctions for violating a United Nations arms embargo on the Houthis.

The Houthis now form the strongest group within Iran's self-described “Axis of Resistance." Others like Lebanon's Hezbollah and the Palestinian militant group Hamas have been decimated by Israel after the Oct. 7, 2023, attack by Hamas that sparked Israel's war of attrition in the Gaza Strip. Allied Shiite militias in Iraq largely have kept their heads down since the U.S. launched retaliatory attacks last year over a drone attack that killed three American troops and injured at least 34 others at a military base in Jordan.

While Iranian state television aired footage of civilian casualties from the weekend strikes in Yemen, top political leaders stayed away from suggestion Tehran itself would get involved in the fight. Revolutionary Guard chief Gen. Hossein Salami notably underscored the Houthis made their own decisions — while not offering any warning over what would happen if the strikes killed any members of the Guard's expeditionary Quds Force, who are believed to actively support the rebels on the ground.

“We have always declared — and we declare again today — that the Yemenis are an independent and free nation in their own land, with an independent national policy,” Salami said.

Trump's national security adviser Mike Waltz, speaking to ABC's “This Week” on Sunday, warned Guard officials training the Houthis “will be on the table too” as possible targets for attack.

Meanwhile, Iran is still trying to determine how to respond to a letter from Trump aiming to restart negotiations over Tehran's rapidly advancing nuclear program. Iranian Foreign Ministry spokesperson Esmail Baghaei said Monday officials continue to review the letter and will respond "after investigations are completed.”

Iran's Foreign Minister Abbas Araghchi separately traveled Sunday to Oman, which long has been an interlocutor between Tehran and the West. The Houthis also operate a political office in the sultanate.

The attacks on the Houthis are “a not-so-subtle signal to Iran, as President Trump has been unequivocal in his insistence that Iran return to the negotiating table to deal with its nuclear program,” the New York-based Soufan Center said in an analysis Monday.