Yemen, explained.
A screen broadcasting US President Donald Trump and Saudi Crown Prince Mohammed bin Salman during a demonstration to denounce the Saudi accusation that Yemenis are attempting to attack Mecca, 18 September 2026, in Sana'a, Yemen (Mohammed Hamoud/Getty Images)
Riyadh wanted Washington’s help against the Houthis – it has thus far gotten intelligence sharing and little else.
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An America-First approach in YemenAn America-First approach in Yemen
On 6 May 2025, following a weeks-long bombardment on Houthi targets in Yemen, US President Donald Trump declared the fight to be over.
The Houthis, “a band of individuals with advanced weaponry that were threatening (Opens in new window) global shipping”, had – according to the US president – “capitulated (Opens in new window)” and agreed to halt their attacks on maritime traffic in the Red Sea.
In one of the first “America-First” deals of the second Trump administration, the United States had extracted itself from one regional conflict, not fixed (Opens in new window) it. Despite being threatened with annihilation (Opens in new window), the Houthis had suffered limited military degradation. They could also continue fighting Israel, which had been excluded from the agreement. As Trump headed to Saudi Arabia for his first major international trip a week later, observers concluded that Israel had been sidelined (Opens in new window) and left to confront the Houthi threat alone (Opens in new window).
Over a year later, Saudi Arabia now finds itself sidelined and largely alone.
Fighting between the Iran-backed Houthis and Saudi Arabia has reignited in recent weeks, unravelling an informal ceasefire that had been in place since 2022 (Opens in new window). Recent Houthi attacks have targeted Riyadh (Opens in new window) and Mecca (Opens in new window), as well as critical infrastructure sites, including the East-West (Opens in new window) oil pipeline and facilities at Yanbu port (Opens in new window). The Houthis have also declared a blockade on Saudi-linked vessels in the Red Sea and launched (Opens in new window) attacks on Saudi ships (Opens in new window).
Saudi Arabia, for its part, has sought to disrupt (Opens in new window) Houthi operations and reinforcement efforts on the Red Sea coast that offer the group strategic control over the Bab-el-Mandab Strait. Alongside Saudi-backed government-aligned forces, Saudi Arabia has conducted hundreds (Opens in new window) of airstrikes on Houthi positions in south-western Yemen, exacerbating an already-dire humanitarian situation (Opens in new window) in Yemen.
The United States had extracted itself from one regional conflict, not fixed it.
The escalation on Saudi Arabia’s southern border comes amid heightened pressure on Riyadh. The ongoing US war with Iran, and the latter’s blockade of the Strait of Hormuz, has restricted Saudi Arabia’s oil exports, leading Saudi Arabia to shift (Opens in new window) some oil exports to a Red Sea bypass (Opens in new window) – a route that is now being threatened by the Houthis.
Saudi Crown Prince Mohammed bin Salman, Saudi Arabia’s de facto ruler, reportedly called Trump twice (Opens in new window) in September to request military backing against the Houthis. While Trump offered (Opens in new window) intelligence sharing and targeting data, the president has so far rejected new US military operations against the group, claiming that the US–Houthi agreement (Opens in new window) was still in place. For Saudi Arabia, which saw itself designated (Opens in new window) a major non-NATO ally by Washington following a commitment to invest (Opens in new window) $1 trillion in the US economy less than a year ago, it has proven a bitter pill to swallow. As one commentator (Opens in new window) put it, “Riyadh’s bet on Trumpism has failed.”
The US is loath to recommit extensive military resources to Yemen in the near term. Seven months on, the US remains bogged down in a war with Iran that was only supposed to last weeks (Opens in new window). The war, which started off seeking regime change, is now centred on finding a solution to the Strait of Hormuz with a new, more hardline (Opens in new window) Iranian leadership. The White House, meanwhile, faces increased political (Opens in new window) and public (Opens in new window) criticism over the war’s staggering costs ahead of the US midterm elections.
Smoke plumes rise over the Aramco oil terminal at Jizan/Jazan, Saudi Arabia, after Houthi missile strikes launched from Yemen. Satellite image 26 July 2026 (Gallo Images/Orbital Horizon/Copernicus Sentinel Data 2026 via Getty Images)
Washington’s prior counter-Houthi efforts presaged the vulnerabilities exposed during the war with Iran. When the Houthis started attacking maritime targets in the Red Sea in the aftermath of the Hamas-led attacks on Israel on 7 October 2023, I was the Middle East Director for Strategic Planning at the US Office of the Director of National Intelligence. The Houthis, even then, were clearly not a ragtag of sandal-wearing rebels: honing the tactics of asymmetric warfare, the group used low-cost (Opens in new window) drones, cutting Suez Canal traffic by 50% (Opens in new window) in 2024. Operation Prosperity Guardian, the US-led maritime coalition to secure passage through the Red Sea that began in December 2023, struggled to reverse this (Opens in new window) – many shipping companies rerouted around Africa via the Cape of Good Hope to avoid higher insurance (Opens in new window) premiums and Houthi attack (Opens in new window). Even months after the Houthis ceased their attacks, traffic (Opens in new window) was still 60% lower than mid-2023 levels.
Prior campaigns by Washington to attack the Houthi from the air have only had limited (Opens in new window) effects. By the time Trump declared victory, the Houthis had moved critical assets to underground bunkers while continuing (Opens in new window) to fire low-cost drones and missiles at ships (Opens in new window) in the Red Sea. Meanwhile, the US burned through precision (Opens in new window) munitions, raising further (Opens in new window) concerns among military (Opens in new window) planners on stockpiles and readiness in the Indo-Pacific. (Opens in new window) Just as the Iranians have shown in recent months, the Houthis’ use of precision mass (Opens in new window) – the deployment of accurate weapons alongside low-cost scalable systems – is a poor (Opens in new window) match for the limited, costly interceptor systems used by the US and its regional allies.
Saudi Arabia has now pinned its hopes on other partners. France has announced (Opens in new window) the deployment of troops and radar systems to protect operations at Yanbu to help minimise further energy price hikes. The UK, for its part, has pledged (Opens in new window) a “purely defensive” effort focused on refuelling (Opens in new window) Saudi aircraft. Meanwhile, Saudi Arabia’s recently penned military pact (Opens in new window) with Pakistan and Türkiye has seen its first real test. Even though the pact has not directly had a coherent operational response, Washington’s recent stance will likely only raise its importance for Riyadh.
About the author
Grace Wermenbol
Grace Wermenbol is a senior visiting fellow at the German Marshall Fund, a senior fellow at the Hague Centre for Strategic Studies, and an adjunct professor at Georgetown University. She is the Executive Director of Boussole Mondiale, a boutique geopolitical analysis firm based in Paris.
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