US strikes against the Houthis in Yemen on 15 March were the heaviest since joint US/UK air operations began in January 2024. They were also the first under the new administration of President Donald Trump. Sending a clear message to Tehran, the president said afterwards that ‘every shot fired by the Houthis will be looked upon…as being a shot fired from the weapons and leadership of Iran’.
The attacks, and Trump’s explicit association of the Houthis with Iran, were not surprising. One of the most important consequences of the wars that followed the 7 October 2023 attacks has been the heightened importance of the Houthis within the Iran-led Axis of Resistance. Since 7 October, their hundreds of attacks on Red Sea shipping, and numerous drone and missile launches against Israel, have formed an important element of the Axis response to the war in Gaza.
Meanwhile, Axis members Hamas and Hezbollah have been badly weakened by Israel during 2024, notably through the decapitation of their leaderships. The Assad regime in Syria collapsed in December, costing Tehran its key state ally in the Axis.
Even Iran has been weakened. Its missile and drone attacks on Israel last year were largely ineffectual as Israeli air defences functioned effectively. In contrast, Israel’s strikes on Iran were surgical: the second attack in October destroyed several air defence sites and a key missile production facility. The message was that in the event of another direct confrontation, Israel could inflict significantly more damage.
The Houthis are the only Axis member to have seen their position strengthened over the last year. The continued fragmentation of Yemen’s internationally recognized government means that the Houthis’ political and military power remains dominant. Their projection of power in the Red Sea has allowed them to establish a global presence. And their attacks on shipping, which they frame as being in solidarity with Palestinians, have embarrassed Arab regimes, whose relative inaction is a source of resentment in their populations.
But it is a mistake to characterize the Houthis as merely an extension of Iran. That perception cannot form the basis of an effective policy.
Iranian support
It is true that the Houthis would not be where they are today without Iran’s support – a relationship that expanded after the Arab uprisings, as a means to counter Saudi Arabia. Even after the Saudi-sponsored truce in Yemen’s civil war of April 2022, Iran’s support has not decreased. In fact, the smuggling of weapons, fuel, and technology to the Houthis has increased, while the Houthis have continued to build up their locally generated military capabilities.
The Houthis’ growing strength undeniably benefits Iran, providing it with a partner on the southwestern tip of the Arabian Peninsula, right beneath its Saudi rival. Iran’s longer-term objective is to see the consolidation and institutionalization of Houthi power, while Tehran continues a ‘hands-off strategy’, exercising a degree of plausible deniability.
In practical terms, this means that Iran encourages the Houthis playing a more important regional role within the Axis. That is why it supports the Houthis in building their regional presence, notably in Iraq and the Horn of Africa.
Diverging interests
That said, there are divergences between Iranian and Houthi interests. The Houthis in particular have demonstrated a much greater tolerance for risk than Tehran. After 7 October, Iran was sceptical about the Houthis launching attacks in the Red Sea, fearing an escalation – yet the Houthis proceeded regardless. Their higher risk tolerance is driven first by excessive confidence – borne out of their dominance inside Yemen and ability to resist years of Saudi and Emirati strikes – and second by their aggressive and expansive ideology. Iran, in contrast, has been careful over the years to calibrate its provocations and to avoid direct confrontation with the US and Israel.
This implies that Iran will hold reservations about the Houthis’ aggressive agenda, especially in the Red Sea. The fear will be that the Houthis could entangle the Islamic Republic in a new round of violence. Moreover, should the truce in Yemen collapse, the prospect of renewed Houthi attacks against Saudi Arabia and the UAE would increase, risking even further destabilizing the region, and threatening the recent warming of relations between Tehran and Riyadh.
Trump’s impact
The arrival of the second Trump administration further changes the equation. The Houthis have already clearly stated that they will retaliate against those who implement the Foreign Terrorist Organization (FTO) designation, announced by Washington in January 2025.
Should this lead to the suspension of fuel imports through the port of Hudaydah (one of the Houthis’ four main sources of revenue), they would likely jettison their commitment to a de facto cross-border truce with Saudi Arabia.
The FTO designation will also compel the Houthis to further steer their economy away from formal banks and towards informal mechanisms, including money exchanges and Hawala transfer systems. They are also already important investors in the crypto world.
