Introduction
The 21st century has witnessed a profound transformation in warfare. Once dominated by nation-states wielding sophisticated armies, navies, and air forces, contemporary conflict is increasingly shaped by non-state actors who leverage low-cost technologies and asymmetric strategies to challenge established powers.[1] The Houthis of Yemen represent a critical case study within this context. Despite the overwhelming presence and power of the United States Navy and its allies in the Red Sea and Gulf of Aden, the Houthis have nonetheless managed to disrupt shipping lanes, damage advanced warships, and force global commercial rerouting in more than 100 attacks since October 2023.[2]
This is not simply a regional security issue; it requires an in-depth analysis of force projection by non-state actors in the contemporary context. The Houthis in Yemen have worked hard to improve their military potential, primarily with the support of Iran, and have added drones, Hatam-2 missiles, and Asef anti-ship missiles to their arsenal.[3] Understanding how the Houthis have increased their conflict potential is crucial for anticipating future conflicts where insurgent groups, militias, or transnational movements may adopt similar methods. This article examines the Houthis’ military innovation, analyzes their asymmetric tactics in maritime spaces, and evaluates the global implications of non-state actors acquiring such capabilities.
Who are Houthis?
The Houthis, formally known as Ansar Allah, are a Zaydi Shia movement in northern Yemen who have fought against Yemen’s Sunni majority government since 2004. Their conflict with the Yemeni government escalated into civil war in 2014 with regional spillover implications.[4] Before the Israel-Palestine conflict started in October 2023, the Houthis were primarily treated as a local Yemeni group with a localized agenda, but this perspective changed in October 2023, “when the Houthis launched a first wave of missiles and uninhabited aerial vehicles (UAVs) against targets in Israel, ostensibly in solidarity with the Palestinians in Gaza.”[5]
The Houthis’ Technological Adaptation and Capabilities
Years of resistance to aerial bombardment, naval blockades, and foreign-backed offensives forced the Houthis to innovate militarily, blending guerrilla warfare with modern technological tools. This resilience laid the groundwork for their subsequent ability to contest maritime spaces in the Red Sea and Gulf of Aden, hence challenging the U.S. and its allies’ power in the region.[6] The most prominent tools in their hands are drones, UAVs, ballistic missiles and unmanned surface vehicles (USVs).
Drones and UAVs
The Houthis’ adaptation of drones in 2016 represents one of their most notable strategic innovations. The militant group began with rudimentary systems, but they now have long-range UAVs capable of both surveillance and offensive operations. While many designs appear to draw on or originate from Iranian technology, the Houthis have increasingly demonstrated their own capacity for manufacturing and modification. In July 2019, Houthi forces unveiled a collection of UAVs, including the Samad 2 and Samad 3, which they claimed to have manufactured domestically, followed by an Iranian propaganda video projecting the same UAVs, further confirming the Iranian origins of UAVs used by Houthis.[7]
Employed for reconnaissance and combat, these drones enable accurate targeting of naval and commercial vessels, while armed variants pose direct threat to warships and critical economic infrastructure.[8] According to Global Terrorism Trends and Analysis Center (GTTAC) data, between 2018 to 2024 the Houthis conducted 388 drone attacks targeting a wide array of actors, including the Yemeni government, Saudi Arabia, the United Arab Emirates, Israel, U.S. military forces, and international commercial and naval vessels in the Red Sea and Gulf of Aden.[9]
Anti-Ship Missiles
The Houthis also possess cruise and ballistic missiles,[10] including Soviet-, Chinese-, and Iranian-made missiles that they have used from time to time. Among their most advanced systems is the Asef anti-ship ballistic missile (ASEF), reportedly of Iranian origin and capable of delivering a 500 kg warhead over 400 km with an electro-optical seeker for terminal guidance.[11] They also field the al-Mandeb 2, an anti-ship cruise missile closely resembling the Chinese C802, which Iran reverse engineered into the Noor variant. With a 120 km range and a 165 kg warhead, the al-Mandab 2 has been deployed against commercial and military vessels since 2016.[12] While the Houthis assert domestic production of such systems, U.S. sources maintain that Iran either supplies the weapon directly or provides critical assistance.[13]
Unmanned Surface Vehicles
Perhaps the most innovative tool in the Houthis’ arsenal is their fleet of unmanned, remote-controlled explosive boats, also known as USVs. They first used USVs in 2017 against Saudi Arabia.[14] They usually use the USVs in combination with missiles to increase the intensity of their offensive.[15] The USVs are frequently disguised as fishing vessels commonly found in the Red Sea and are made of wood or fiberglass. The USV was used in a recent attack in Red Sea in June 2025.[16]
Asymmetric Tactics and Strategic Logic
The Houthis have taken advantage of weaknesses in advanced naval platforms by using cheap drones, precision-guided missiles, and unmanned surface vehicles. The Houthis don’t need a lot of money, training, or logistics like traditional fleets do. Instead, they rely on their own creativity and outside support networks. Their tactics demonstrate a change in naval warfare for smaller belligerents from ship-to-ship battles to swarm attacks, electronic disruption, and attritional harassment.
By targeting both commercial and military ships with these strikes, they disrupt naval operations and weaken the stability of the global supply chain. Even attacks that don’t work out force the other side to use more expensive defensive weapons.[17] This method is similar to guerilla warfare in that it uses attrition, symbolic wins, and asymmetric pressure instead of direct confrontation. The use of USVs at sea are an example of these guerrilla tactics as they are hard to find, not too expensive to make, and can do a lot of damage to warships or commercial carriers.
The Houthis’ popular support has significantly increased after their acts in Red Sea. By forcing the rerouting of commercial vessels around the Cape of Good Hope they have increased shipping costs, delayed supply chains, and undermined confidence in maritime security. The group has built an image of strength and resistance against outside interference by effectively challenging the naval superiority of the U.S. and its allies. Their ability to disrupt global transportation routes and hurt superior militaries has struck a chord with people at home, who see these activities as a sign of sovereignty and resistance. These actions have also helped the Houthis gain credibility in the region by supporting broader anti-Western and anti-interventionist narratives. This has allowed them to present themselves as a leading force in standing up to global powers on behalf of neglected groups. The U.S. launched its biggest air and naval offensive against the Houthis in March 2025,[18] but despite the damage to the Yemeni group their ability to threaten marine trade can still change the course of regional negotiations and improve their bargaining position with Saudi Arabia, the UAE, and Western nations.
Way Forward
The Houthis have shown how non-state actors can use cheap tools and strategies to impose costs on more powerful opponents. This changing situation points to four critical areas that the states should focus on:
Maritime security doctrines should prioritize dealing with asymmetrical threats. Governments in the region should work together to create a maritime security system that is adaptable and can handle the unusual technologies and tactics utilized by non-state actors like Houthis.
Iran’s ongoing assistance has been very important for the Houthis, demonstrating how outside actors can provide non-state actors with more asymmetrical powers. Governments should engage in dialogue with these outside actors to prevent this assistance.
States need to add more tools to their defensive toolkits, especially on ways to stop drone assaults on land and at sea.
Governments need to deal with the political reasons behind war, as non-state actors like the Houthis utilize these kinds of techniques to authenticate their political cause and gain support from their people. The technological remedies should be complemented by political resolutions to the dispute.
Disclaimer:
The views and opinions expressed in the INSIGHTS publication series are those of the individual contributors and do not necessarily reflect the official policy or position of Rabdan Security & Defense Institute, its affiliated organizations, or any government entity. The content published is intended for informational purposes and reflects the personal perspectives of the authors on various security and defence-related topics.
[1] Colonel Dave Wallace and Major Shane Reeves, “Non-State Armed Groups and Technology: The Humanitarian Tragedy at Our Doorstep”, University of Miami National Security & Armed Conflict Review. 26 (2013), https://repository.law.miami.edu/umnsac/vol3/iss1/4/
[2] Paulo Aguiar, “Houthis Emerge from Red Sea Crisis Unscathed”, Situational Report, February 19, 2025, https://www.geopoliticalmonitor.com/houthis-emerge-from-red-sea-shipping-crisis-unscathed/
[3] Ibid.
[4] “Who are Yemen’s Houthis”, Insights and Analysis by Wilson Center, July 2022, https://www.wilsoncenter.org/article/who-are-yemens-houthis
[5] Wolf-Christian Paes and others, “Navigating Troubled Waters: The Houthis’ Campaign in the Red Sea and the Gulf of Aden”, Research Paper by IISS, December 2024, https://www.iiss.org/research-paper/2024/12/navigating-troubled-waters-the-houthis-campaign-in-the-red-sea-and-the-gulf-of-aden/
[6] “Six rescued, 15 missing after Houthi attack on cargo ship in Red Sea”, Al-Jazeera, July 9, 2025, https://www.aljazeera.com/news/2025/7/9/five-rescued-after-suspected-attack-by-yemens-houthis-on-red-sea-vessel
[7] “Evolution of UAVs Employed by Houthi Forces in Yemen”, Dispatch from the Field, Conflict Armament Research, February 2020, https://www.conflictarm.com/dispatches/evolution-of-uavs-employed-by-houthi-forces-in-yemen/
[8] Ibid.
[9] Suat Cubukcu and Evan Jordan, “The Houthis Drones Supply Chain”, Research Report, Orion Policy Research Institute, July 2025, https://orionpolicy.org/the-houthi-drone-supply-chain/
[10] “Houthis Arsenal”, Wilson Center Report, July 2024, https://www.wilsoncenter.org/article/houthi-arsenal
[11] For more details please see, Fabian Hinz, “Houthi anti-ship missile systems: Getting Better all the Time”, Military Balance Blog, IISS Publication, January 2024, https://www.iiss.org/online-analysis/military-balance/2024/01/houthi-anti-ship-missile-systems-getting-better-all-the-time/ Sam Cranny-Evans and Dr Sidharth Kaushal, “Securing the Red Sea: How Can Houthi Maritime Strikes be Countered?”, Commentary by RUSI, January 2024, https://www.rusi.org/explore-our-research/publications/commentary/securing-red-sea-how-can-houthi-maritime-strikes-be-countered
[12] Sam Cranny-Evans and Dr Sidharth Kaushal, “Securing the Red Sea: How Can Houthi Maritime Strikes be Countered?”, Commentary by RUSI, January 2024, https://www.rusi.org/explore-our-research/publications/commentary/securing-red-sea-how-can-houthi-maritime-strikes-be-countered
[13] Ibid.
[14] Christopher P. Cavas, “New Houthi Weapon Emerges: A Drone Boat”, Defense News, February 19, 2017, https://www.defensenews.com/digital-show-dailies/idex/2017/02/19/new-houthi-weapon-emerges-a-drone-boat/
[15] “Six rescued, 15 missing after Houthi attack on cargo ship in Red Sea”, Al-Jazeera, July 9, 2025, https://www.aljazeera.com/news/2025/7/9/five-rescued-after-suspected-attack-by-yemens-houthis-on-red-sea-vessel
[16] Howard Altman, “First Look At Houthi Kamikaze Drone Boat That Struck Cargo Ship In Red Sea”,
[17] Mohamed ELDoh, “Why the Houthis Threat Persists?”, Global Security Review, https://globalsecurityreview.com/why-the-houthi-threat-persists/
[18] “US fires on Sanaa as campaign against Yemen’s Houthis continues”, Al-Jazeera, March 24, 2025, https://www.aljazeera.com/news/2025/3/24/us-fires-on-sanaa-as-campaign-against-yemens-houthis-continues
