Drone Warfare Comes to the Gulf: How Unmanned Systems Are Changing the Tanker Threat
The 2019 attack on the Abqaiq oil processing facility used cruise missiles and drones. The subsequent attacks on tankers in the Gulf of Oman used limpet mines and, in some cases, explosive-laden fast boats. By the time Houthi forces began their Red Sea campaign in late 2023, the weapons mix had evolved to include one-way attack drones and ballistic missiles fired against commercial vessels. The technological trajectory is consistent: unmanned systems are becoming a larger share of the threat to shipping in and around the Persian Gulf, and their characteristics — low cost, deniability, saturation potential, and steadily improving accuracy — make them a structural shift rather than a tactical adaptation.
The economics of drone warfare applied to shipping are favorable to the attacker. A commercially derived one-way attack drone, modified with a warhead and basic guidance, costs tens of thousands of dollars. The vessel it targets may be worth tens or hundreds of millions. The insurance claim, the rerouting cost, and the price spike that a successful attack triggers multiply the economic damage well beyond the value of the destroyed cargo or hull. The IRGC and its proxy forces have internalized this cost asymmetry and have invested accordingly in drone production capacity, range extension, and warhead optimization for anti-ship applications.
The Iranian drone program’s maritime application builds on a decade of aerial drone development that has produced weapons systems transferred to Hezbollah, the Houthis, Iraqi militias, and other proxy forces throughout the region. The Shahed-series drones, which achieved international notoriety through their use in the Russia-Ukraine conflict, are relevant here because they demonstrate Iran’s ability to produce unmanned systems at scale, transfer them across international borders, and sustain a proxy force’s ability to conduct sustained aerial attack campaigns. The same production and logistics infrastructure supports maritime drone operations in the Gulf.
The surface drone dimension is less developed but increasingly concerning. Explosive-laden unmanned surface vessels — essentially boat bombs with remote or autonomous guidance — have been demonstrated in Houthi operations against Saudi naval vessels. Applied to tanker attack scenarios in the strait, an unmanned surface vessel offers advantages over a manned fast attack craft: no crew to lose, lower radar cross-section in some designs, and the ability to approach a target slowly over a long period without the behavioral signatures that would alert a security-conscious crew. The detection and interception problem for coalition naval forces is genuinely harder than it is for manned fast boats whose crews must make visible approach decisions.
The defensive response to drone threats at sea has struggled to keep pace. Ship-mounted close-in weapons systems — Phalanx, SeaRAM — were designed for anti-missile defense and have been adapted for drone intercept with varying success. The engagement geometry for slow, low-flying drones is different from the high-speed, high-altitude missile threat these systems were optimized against. Electronic countermeasures — jamming GPS and communications links that some drones depend on — provide partial protection against less sophisticated systems but are ineffective against inertially guided or optically guided weapons that do not rely on external signals. The defensive gap is real.
Commercial shipping vessels are almost entirely undefended against this threat. The armed security personnel that became standard on merchant vessels transiting the Gulf of Aden during the piracy era provide no meaningful defense against armed drones. The hardening of commercial vessels against drone and missile attack would require capital expenditure and design changes that the industry has not been willing to make in the absence of regulatory requirements, and that flag states have not imposed. The gap between the offensive capability that Iranian-linked forces have demonstrated and the defensive capability of the vessels they can target has been widening for several years.
The drone threat in the Gulf is not a future contingency. It is a present reality whose implications for shipping risk and insurance pricing are still being incorporated into the market’s assessment of what it costs to move a barrel of oil through the world’s most important waterway.