Iran’s Support of the Houthis: What to Know

Yemen’s Iran-aligned Houthi movement is emerging as one of the Middle East’s most potent nonstate actors as Israel’s war against Hamas rages on in the Gaza Strip. The group’s ability to maintain disruptive strikes in the Red Sea raises fresh questions about the extent of its ties with Iran.

Who are the Houthis?

The Houthis are a local rebel movement that currently rules a third of Yemen’s territory and two-thirds of its population. They revolted against the internationally recognized government in 2011 and overthrew it in 2014. Yemen’s civil war continues today, with its front lines largely frozen. The Houthis’ government, based in the capital, Sanaa, is recognized only by Iran. Influenced by strict readings of Islamic law and local caste-based traditions, Houthi governance is considered repressive by human rights watchdogs. The Houthis’ infamous, Iranian-inspired rallying cry points to their ambitions beyond Yemen: “God is great, death to America, death to Israel, a curse upon the Jews, victory to Islam.” The United States designates them as a terrorist group.

The Houthis are formally known as Ansar Allah (Supporters of God in Arabic), but their popular name refers to the movement’s leaders, who come from northern Yemen’s Houthi tribe. Originally a political movement, the Houthis militarized in the late 2000s, fighting wars against Yemen’s government. They command some twenty thousand fighters, a mix of tribal forces and troops formerly loyal to the government. The Houthi movement is rooted in Zaidism, also known as “Fiver” Shiite Islam, meaning it recognizes only the first five of the Prophet Mohammed’s successors. It is practiced mainly in northern Yemen, where it has also taken on elements of Sunni Islam. Zaidis compose around a third of Yemen’s population of thirty-four million.

How did the Houthis become aligned with Iran?

By some experts’ estimations, Iranian military support to the Houthis began as early as 2009, amid the Houthis’ first war against Yemen’s government. Most experts agree that the Houthis were receiving weapons from Iran by 2014, the year they captured Sanaa. In both cases, military intervention against the Houthis by Iran’s regional rival, Saudi Arabia, likely catalyzed Tehran’s increased interest in the group.

Militant groups allied with Iran are frequently called Tehran’s proxies, but many experts say the Houthis are better characterized as Iran’s willing partner [PDF]. Iran’s model of “exporting” its 1979 Islamic Revolution by cultivating armed groups in the region allows these groups a degree of flexibility, the Washington Institute for Near East Policy’s Michael Knights tells CFR. “It doesn’t tend to force groups like the Houthis to choose between what they want to do locally and the Iranian model,” he says. However, the Houthis and the Islamic Republic share an ideological affinity [PDF] and geopolitical interests that motivate the Houthis to assist Iran. “They don’t have to be told, they don’t have to be coerced, they don’t even really have to be bribed. They’re a very loyal fellow traveler to the Islamic Revolution in Iran.”

While the Houthis hold Iran’s supreme leader and the Islamic Revolution in high esteem, notable differences separate them from Iran and its closest partners. The Houthis don’t practice the “Twelver” Shiism prevalent in Iran, though they have reportedly incorporated Twelver beliefs into their interpretation of Zaidism. They also weren’t founded with Iran’s help, as groups including Lebanon’s Hezbollah and Iraq’s Badr Organization were. And unlike with some Iran-backed groups, Houthi leader Abdul-Malik al-Houthi reportedly doesn’t see himself as subordinate to Iran’s supreme leader.

How extensive is the military relationship?

Iran is the Houthis’ primary benefactor, providing them mostly with security assistance, such as weapons transfers, training, and intelligence support. In late January 2024, for example, U.S. forces intercepted a shipment carrying military aid from Iran to the Houthis, including drone parts, missile warheads, and anti-tank missile units. Such aid mainly reaches the Houthis via Iran’s paramilitary Islamic Revolutionary Guard Corps (IRGC).

In return for Iran’s aid, the Houthis serve as an increasingly important part of Iran’s “axis of resistance," a network of state and nonstate actors seeking to undermine Western influence in the Middle East. That mission involves pushing the United States out of the region, destroying Israel, and intimidating those countries’ regional partners. The Houthis regularly engage with leaders from across the alliance, especially Hezbollah, Knights says, and that group provides the Houthis with support at Iran’s behest. In addition, IRGC and Hezbollah representatives advise the Houthis’ military command authority, the Jihad Council, though their influence on Houthi decision-making is unclear, Knights wrote [PDF] in 2022.

For the Houthis, the Iran connection provides more sophisticated weaponry than they could acquire on their own, especially missiles and drones. Iranian support has bolstered the group’s fighting abilities, helping the Houthis gain and maintain military superiority within Yemen, but experts say it has had greater impact elsewhere. “The role of Iran has been decisive in providing the Houthis with smuggled weapons and expertise to project power into the Red Sea and Bab al-Mandab Strait,” Gulf analyst Eleonora Ardemagni writes for the Yemen-based Sana’a Center for Strategic Studies.

The Houthis assist Iran by menacing Saudi Arabia’s border and protecting Iranian ships in the Red Sea, giving Iran room to evade sanctions on oil shipping, Iran expert Mohammad Ayatollahi Tabaar writes in Foreign Affairs. At the same time, the Houthis help field test Iranian-made weapons on Yemen’s front lines and in the Red Sea. Like all axis members, the Houthis offer Iran plausible deniability; members routinely claim responsibility for attacks likely ordered or perpetrated by Iran. For instance, many experts blame Iran for attacks on Saudi Arabia’s oil facilities that the Houthis claimed in September 2019.

How have ties been affected by the Israel-Hamas war?

In what the Houthis are calling a show of support for Hamas and Palestinians, the group has attacked supposed U.S.- and Israel-linked targets in the Red Sea and even fired missiles at Israel, with ruinous effects for international shipping. Experts say it is unclear whether Iran or Houthi leaders ordered the initial strikes, but Tehran has voiced its unequivocal support for the operations and reportedly assists the Houthis in targeting vessels. The Houthi threat in the Red Sea concerns Washington especially, as freedom of navigation is a core U.S. interest. In response, the United States is working with the United Kingdom to bomb Houthi targets in Yemen, and U.S. and European Union naval missions are protecting ships in the Red Sea.

But efforts to halt the attacks have been unsuccessful so far and have instead highlighted the strength of Iran’s axis of resistance. At the same time, experts say, the war is boosting the Houthis’ status among Iran’s partners and raising their reputation in Yemen and beyond. In a December report, the Sana’a Center’s editorial board wrote, “For the Houthis, this is a golden opportunity to capitalize on widespread support for the Palestinian cause to raise their flagging popularity inside territories under their control, while pressing their case to the outside world that they are the only effective authority in Yemen.”