How do drone attacks on merchant ships work and who is responsible?

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1. 1

   The Red Sea Crisis: ramifications for vessel operations, shipping networks, and maritime supply chains

   Maritime Economics & Logistics (Notteboom et al.)Published Feb 20, 2024Checked Oct 13, 2026

   “The attack of Hamas on Israel of October 7, 2023, and the military response of the latter in Gaza have made news headlines for much of the last quarter of 2023 and early 2024. The international community has attempted to prevent escalation and the spreading of the conflict to other parts of the Middle East and the wider world. Despite those efforts, a major security situation emerged in mid-November in the Red Sea and the Strait of Bab al-Mandab more specifically (map in Fig. 1 ), when Houthi Rebels based in Yemen started to target international shipping transiting through the region. In a matter of weeks, the situation escalated, adversely affecting both shipping and trade.”

2. 2

   The Red Sea as A Proxy Front: Iran’s Strategic Use of The Houthis and The Politics of Plausible Deniability (2023–2025)

   International Journal of Social Science & Entrepreneurship (israr & Ghani)Published Sep 30, 2025Checked Oct 13, 2026

   “The Red Sea has become one of the most strategically consequential maritime theaters in the 21st century, where regional rivalries, proxy warfare, and asymmetric operations converge to shape global economic and security outcomes. Between 2023 and 2025, this corridor became a critical arena for Iran’s regional power projection through its sponsorship of Yemen’s Houthi movement. During this period, 145 Houthis attacks including drone, missile and unmanned naval strikes on commercial vessels such as the Magic seas and Eternity C disrupted maritime traffic, caused a 50% decline in Suez Canal transit, and significantly raised insurance premiums. The study adopts a qualitative case study approach, applying proxy warfare theory and drawing on official reports, open-source intelligence, and secondary literature to trace how Iranian support shapes Houthi capabilities. The findings indicate that these operations undermine energy security, threaten freedom of navigation, and compel regional and international actors to recalibrate maritime strategies. Keywords: , , , , , , ,”

3. 3

   Ship sinks in new drone attack off Bulgaria, PM summons Russian ambassador

   BBC NewsPublished Oct 13, 2026Checked Oct 13, 2026

   “Bulgaria's prime minister says two merchant ships were hit by drones and he suspects Russia was behind the attacks.”

4. 4

   Iran and Its proxies: attribution and state responsibility

   CentAUR (University of Reading) (Maddocks)Published Oct 15, 2025Checked Oct 13, 2026

   “Yet the Houthis' attacks on Israel and against Red Sea shipping demonstrate how Iran's support to these groups continues to facilitate their conduct in violation of international law. This article examines Iran's potential responsibility for acts on the part of its proxies that violate its international legal obligations. It assesses first the grounds on which the proxies' acts could be attributable to Iran before addressing Iran's potential responsibility for aiding and assisting its proxies' harmful conduct. Finally, the article considers Iran's potential breach of primary norms of international law, such as the prohibition on the use of force, through its support to the proxy groups. The analysis highlights the varied relationships between Iran and its proxies and the difficulties that arise when seeking to hold Iran to account. Many of the proxy groups act with a degree of independence that precludes the attribution of their conduct to Iran. Other States might therefore be better served by calling Tehran out for its violation of primary norms of international law, including Common Article 1 to the Geneva Conventions.”

5. 5

   Challenges and Security Risks in the Red Sea: Impact of Houthi Attacks on Maritime Traffic

   Journal of Marine Science and Engineering (Rodríguez et al.)Published Oct 23, 2024Checked Oct 13, 2026

   “The findings reveal a marked decline in maritime activity in the Gulf of Aden and Suez Canal, attributed to security concerns stemming from Houthi attacks, with a significant shift towards alternative routes, notably around the Cape of Good Hope. This shift underscores the broader implications of regional instability on global trade dynamics and the critical nature of maintaining uninterrupted maritime flow. The study also highlights the economic ramifications, including increased operational costs and freight rates due to longer transit times and enhanced security measures. It concludes with a call for improved maritime security protocols and international cooperation to safeguard these strategic maritime pathways. This research contributes to the discourse on transport geography by quantifying the direct impacts of regional conflicts on maritime logistics and proposing strategies for future resilience, emphasizing the intertwined nature of global trade, security, and the urgent need for collective action in the face of evolving geopolitical challenges.”

6. 6

   The Legality of the Defensive Measures Taken by the USA and the UK in Response to the Houthi Attacks

   Lexonomica (Glavica & Brulc)Published Jan 1, 2024Checked Oct 13, 2026

   “The article delves into the legality of defensive actions taken by the USA and the UK in response to the Houthi attacks in the Red Sea. Despite assertions that such actions are justified under the right to self-defence, legal ambiguities persist in international law. The authors argue that while attacks on merchant vessels by non-state actors may constitute armed aggression, clarity is lacking on whether they meet the criteria for self-defence. The USA and UK stress that attacks on their warships validate their defensive measures, framing them as necessary responses to significant threats. However, the authors contend that the principle of proportionality may have been disregarded, urging restraint in the use of force to safeguard ships while respecting Yemen’s sovereignty. The article underscores the need for a nuanced approach to assessing the legality and necessity of military actions in complex conflict scenarios.”