Since 2015, when Saudi Arabia launched its intervention in Yemen, the Houthi movement has deepened its ties with Iran and grown more powerful on the ground. As a result, the impact of the Iranian-Houthi partnership will increasingly be felt beyond Yemen’s borders. As I have argued elsewhere, the Houthis are now developing their own foreign policy, forming direct ties with other Iranian partners in the region and presenting a growing risk to rivals like Saudi Arabia and, eventually, Israel. In recent years, some of the most alarmist coverage of the Houthi movement has presented the group in simplistic terms as an Iranian proxy inside Yemen. In fact, the partnership is more complex than a patron-proxy one, but it still carries real risks for regional security.
A Mutually Beneficial Partnership
While the Houthi movement emerged as an insurgency in northwestern Yemen in the 1980s and 1990s, it most likely began receiving Iranian support around 2009. Yet this initial support was marginal, as Yemen at the time was far from an important priority for Iran. Relations ramped up after 2011 as street protests and elite infighting caused an already fragile Yemeni state to weaken even more. Exploiting this vacuum, the Houthis expanded their power and eventually took over the capital, Sanaa, in 2014. These evolving local dynamics piqued Iran’s interest: Saudi Arabia was increasingly anxious at the prospect of mounting insecurity on its vulnerable southern border, while the Houthis were becoming more powerful. Nevertheless, through 2014, Iran’s role in the growth of Houthi power remained limited.
The major turning point came in March 2015 when Saudi Arabia launched a military intervention in Yemen, officially to roll back the Houthis and return the internationally recognized government of President Abdrabbuh Mansour Hadi to power. The intervention has since become an unmitigated disaster: It is a quagmire from which Saudi Arabia has proved unable to extricate itself, even as the Houthis emerged as the dominant actor in Yemen.
It is impossible to precisely quantify how much of the Houthi movement’s success is the result of Iranian support. A significant portion of Houthi assets have been generated locally: Large portions of their arsenal come from absorbing — by negotiation or coercion — units of the Yemeni military, as well as from looting national army stockpiles, forging alliances with tribal militias, and making purchases on the black market.
That said, growing Iranian support has certainly played an important role in helping the Houthis to become more powerful. In addition to providing the group with an increasing number of small arms, Iran has been delivering more advanced and lethal weapons as well. In many cases, Iran uses complex smuggling and procurement networks to provide more technologically advanced parts that the Houthis then combine with other locally acquired or produced ones. They assemble these parts into working weapons with technical assistance from Hizballah and Islamic Revolutionary Guard Corps advisers. This approach has allowed the Houthis to now field short and long-range drones and an increasingly diversified fleet of missiles capable of striking deep inside Saudi Arabia. Houthi forces have also used Chinese-made C-801 anti-ship missiles, with a range of 42 kilometers, for attacks on tankers in the Red Sea. These missiles were part of the national army’s arsenal prior to 2014 and were seized during the war. But they were quite possibly modified further with Iranian or Hizballah assistance.
Any assessment of growing Houthi power should also recognize that the group has immensely benefitted from its adversaries’ weakness. The Hadi government is incompetent, corrupt, and fragmented, and it has little legitimacy among the Yemeni population. The pro-government coalition is barely held together by Saudi support, and its members sometimes fight each other as much as they fight the Houthis. The Houthi movement is also less reliant on Iranian support than the Hadi government is on Saudi Arabia. If Iran cut off its support, the Houthis would remain dominant. If Riyadh cut off its support, the fragile coalition supporting Hadi would collapse.
And as much as it is true that Iran increasingly supports the Houthi movement, it is equally true that Iran has bandwagoned on the Houthis’ successes. Many see the Houthis as Iranian proxies. But this is only part of the story, as the Houthis are also using their ties with Iran to advance their own interests and have been keen to expand relations. They have been under attack by a military force far superior in conventional terms, and only Iran has been willing and able to provide external support. But this does not make them pawns of Iran. There is no evidence, as some Iran hawks allege, that the Houthis take orders from Tehran or would have adopted significantly different policies absent Iranian support.
The Houthi movement’s growing strength is being felt around the region. For very little money, Iran has been able to help the Houthis to significantly increase their ability to pressure Saudi Arabia. The Houthis can now strike infrastructure deep inside the country. Riyadh claims that it has intercepted, as of February 2021, almost 900 Houthi missiles and drones since 2015. This number is impossible to verify, but it is plausible. Admittedly, the military impact of these strikes has been limited and the material damage to Saudi Arabia has been negligible. But the symbolic consequences have been significant, as are the longer-term implications. The key trend is that the Houthis have been steadily improving their ability to inflict damage on Saudi Arabia. As a result, Saudi deterrence vis-à-vis the Houthis — and by extension, Iran — will continue weakening.
The Houthi movement is now increasingly vocal and assertive in its ambition towards southwestern Saudi Arabia. Some of its leaders claim that the Saudi provinces of Jizan, Asir, and Najran historically belong to Yemen, while Houthi forces have been able to mount a sustained campaign of cross-border incursions. They have even occupied small parcels of land and forced the evacuation of Saudi villages close to the border.
The Houthis do not yet appear to have acquired missiles or drones capable of reaching Israel — this would require a range of about 1,800 kilometers, whereas their longest-range assets currently have a range of about 1,500 kilometers. It is likely, however, that they will obtain this capability in the short to mid-term. Not surprisingly, Israel’s interest in — and threat perception relative to — Yemen has steadily increased in recent years.
This growth of the Iranian-Houthi partnership should also be seen in the broader context of Iran’s foreign policy. Until recently, Iran’s relations with the web of non-state armed actors it supports followed a hub-and-spokes model with Iran at the center. This dynamic, however, is evolving: Iran remains firmly at the center of this constellation of revisionist actors, but the spokes — Hizballah, Hamas, the Houthis, and various Syrian and Iraqi militias — are increasingly developing ties directly to each other. They are not bypassing Tehran, but rather developing their own foreign relations. This is a trend, importantly, that Tehran actively encourages. It is not a sign of a weakening of its influence — to the contrary, it indicates the growing maturity of the network. Hizballah has been at the forefront of this evolution, with a growing role in Syria, Iraq, and now Yemen.
The Houthi movement’s role in this network of Iran-backed non-state actors has grown to the point that it is now possible to refer to Houthi foreign policy. Houthi-Hizballah ties have become particularly prominent, as the two movements increasingly cooperate in areas ranging from training to weapons smuggling. Yemen is also, according to some reports, increasingly used as a platform for Iran to send weapons to other armed groups it supports, most notably Hamas. In this case, weapons delivered to Yemen are transshipped to Sudan and then through Egypt to the Gaza Strip. There is also evidence that Iran and Iranian-backed groups are increasingly coordinating their information operations, for example in the immediate aftermath of recent missile and drone attacks against Saudi Arabia.
The Houthi movement is now a regional power, demonstrating ever greater experience and skill as it pursues its interests in the region. The Houthis have emerged from Yemen’s civil war as an increasingly important element in the Iranian-led constellation of revisionist actors that surrounds Saudi Arabia and Israel. They also provide Iran with new options for targeting American forces in the Middle East. Houthi leaders will not attack Iran’s enemies solely based on orders from Tehran — that is not how their partnership functions. In a hypothetical escalation, the Houthi leadership would have to balance its multiple interests, notably the need to preserve Iranian support, the risk of American retaliation, and the politics of maintaining their position inside Yemen. Nonetheless, the Houthi’s newfound reach has enhanced Iran’s deterrence posture and its ability to project power — all at very little cost to Tehran.