*This article also appears as a chapter in the 2023 KCIS Conference volume

On January 28, 2024, an Uncrewed Aerial Vehicle (UAV) attacked a military base near the Syrian border in Jordan, resulting in the deaths of three U.S. soldiers and injuries to over 40 other service members. [AB1] This followed on from a drone having targeted an American base in Erbil, Iraq, in late October, which did not explode. Barbara Slavin, an academic expert on the Middle East, stated that “this was a tragedy that in hindsight, looks to have been inevitable.”[1] The inevitability of the rising number of violent attacks by autonomous vehicles rings true.

In the five months since the outbreak of the Israel-Gaza conflict on 7 October 2023, there have been more than 200 incidents of ‘drone’ and rocket attacks and attempted attacks on U.S.[AB2]  and Global Coalition forces across the Middle East; of these strikes, 114 were Unmanned Aerial Vehicles (UAV) attacks.[2] This is a 20-fold increase compared to the preceding four-month period. In the entire 12 months before 7 October, only about 30 similar events had been reported in the region. Armed or explosive-laden UAVs are decreasingly newsworthy though; the Western population seems to have gotten its fill from the nightly news out of Afghanistan and Iraq.

The development of uncrewed maritime systems (UMSs), however, has seen vast growth. UMSs are distinguished, obviously, by the environment in which they operate: on the surface of the water (uncrewed surface vehicles or USVs) or beneath it (uncrewed underwater vehicles or UUVs), which can operate both on and under the surface. Within these two categorisations, UMSs can be distinguished according to characteristics such as their size, displacement (weight), speed, range and, for underwater systems, operating depth, and whether or not they are armed.

Such systems are likely to pose significant international security challenges. General maritime security challenges, which due to the maritime domain being vast and difficult to monitor, will be exacerbated by the mere presence UMSs making tracking more difficult. Other challenges are specific to UMSs, notably in terms of how the inevitable proliferation and misuse of these systems, particularly by non-state actors, will further affect overall security.

In general, being uncrewed provides several benefits. For example, absent required space for an operator and crew, expanse becomes available for other features or payload, or conversely, the vessel can be made smaller decreasing its likelihood of detection. Additionally, the risk to the life of the UMV operator is lowered or even eliminated compared to that of a crewed vessel if attacked. Finally, another difference relates to the types of tasks undertaken; uncrewed systems can be used for more dangerous taskings, such as minesweeping and activities requiring more depth of operation, as well as for longer-duration missions.[3]

This chapter/contribution will consider the historical background and contemporary usage of these maritime vessels, followed by reflecting upon some concerns, which range from legal and policy issues up to fears of killer robots running amok. The conclusion will include a table of acronyms because, being a new military technology, it is awash with buzzwords and an alphabet soup of abbreviations. The relevance of this document lay in that Canada has committed to acquiring several varieties of remotely-piloted systems. These will include undersea systems for conducting acoustic surveillance, mapping or the surveillance of ‘chokepoints,’ and naval mine countermeasures.[4]  But first, let us clarify some definitions.

The term UMS encompasses both the vehicle (the uncrewed maritime vehicle, UMV) and the control system that enables its remote operation. In the context of this primer, “autonomy” refers to the autonomy of a vehicle’s navigation and object-identification functions enabled by artificial intelligence (AI), rather than the rules-based automation, or autonomy underlying the use of a vehicle’s potentially lethal payload.[5]

Compared to an automated navigation system that executes a pre-defined route, an autonomous navigation system will adapt. It may temporarily deviate from the route when other automated functions, such as collision avoidance or lost communications, indicate that the situation requires it. Here too, operator supervision and intervention are typically required, but various options for the allocation of authority between the system and the operator are possible, as seen in this Level of Automation (LoA) framework.[6]

Table 1. Eight Levels of Automation

Looking to the past, the idea of using expendable vessels as weapons is not new; for centuries, navies would set old ships aflame—“fire ships” —and allow them to drift down current to burn their enemies. More recently, self-sacrificing individuals have driven vessels into targets and detonated them, as in the attack against the USS Cole (Arleigh Burke-class DDG) in 2000. The growing availability and capabilities of UMVs, however, enable vessels to be guided weapons without the assured sacrifice of personnel.

In modern history, the development of UMVs came before that of other unmanned systems. An electrically controlled boat was used in experiments conducted by the British torpedo ship HMS Vernon as early as 1885. But these early attempts led to no practical results because at that time no suitable motors were available, and transmission of electric power was still in its infancy.[7]

The first remotely controlled vessel of any kind was the Teleautomata, a USV developed and tested by Nikola Tesla in 1898.

Germany had some successes with USVs in the First World War in their experiments with remote control from land, ships, and airplanes, using cables as well as radio. In 1915 twelve boats were ordered for coastal defence. This was followed shortly thereafter by five additional boats, so that a total of 17 electrically controlled motorboats were built and used by the Germans during the war. These 42-foot boats, equipped with twin gasoline engines could attain a speed of 28 to 30 knots, with their fuel capacity allowing them to travel for about 6 hours at full speed.[8]

In 1944, Germany used a remotely controlled USV filled with explosives to target Allied shipping. USV development proceeded relatively slowly from the post–World War II period until the 1990s, although there was some usage by the U.S. Navy and others for testing, training, and mine countermeasures (MCM).[9]

The predecessors of today’s UMVs during the Cold War were limited to minesweeping and sample collection from Nuclear, Biological, Chemical Warfare (NBCW) contaminated sites. In the early-2000s, minimizing the risk to personnel by using uncrewed vehicles in “dull, dangerous, or dirty” missions were seen as the main focus of development.[10] The past two decades have witnessed considerable developments with respect to all unmanned systems, leveraging advances in information technology, remote-control capabilities, the Global Positioning System for navigation, and materials science. In recent years, military use of unmanned systems—in the air, on the ground, on and under the waterline —has increased dramatically, a trend that military leaders and experts expect to continue.

Naval warfare in the new millennium is anticipated to primarily operate near the shore, aiming to project power inland, offer defensive coverage for onshore forces, and provide security against threats, such as coastal piracy. For this purpose, mines, conventional submarines, small boat swarms and surface cruise missiles are anticipated to play a prominent role. UMV mission sets are likely to include:

• Coastal and harbour defence, mine-laying in the vicinity of enemy ports and/or critical narrow waterways

• Mine Countermeasures (MCM)

• Anti-submarine warfare (ASW)

• Anti-surface warfare (ASuW)

• Anti-air warfare (AAW)

• Maritime special operations (SOF) support, intelligence, surveillance

• Reconnaissance (ISR) in critical maritime zones, payload transport communications/navigation network nodes (CN3)

• Electronic warfare (EW)

• Peacetime maritime surveillance operations, and the use of conventional weapons against high-value targets. [11] [AB3] [r.4] 

UMVs will likely play critical roles in battlespace preparedness and awareness, in addition to gathering oceanographic details that may aid military systems, as well as identifying NBCW substances – all relevant ISR tasks.[12]

An example of conventional weapons use against high-value targets would be Ukraine’s October 2022 attack on the Kerch Strait Bridge between Crimea and Russia. Ukraine not only diminished Russian logistics access, but also achieved a pronounced morale victory. The longest bridge in Europe was Vladimir Putin's pet project; Ukrainians swiftly mocked “having put on a dramatic ‘fireworks show’ that damaged a large swath of the bridge for Putin's 70th birthday.”[13] Such large-scale infrastructure is hard to seriously damage, having been designed to withstand a variety of environmental stresses and the rigors of regular usage. Expert reviews of video and photographic evidence suggest that the initial explosion likely came from below. Divers placing adequate explosives would have required numerous clandestine trips, which suggests that UMVs could conceivably have been used; this hypothesis is supported by evidence that Ukraine is already using explosive-laden USVs.[14] Effectively, Ukraine has shown the capability of UMVs to conduct successful missions against high-value targets of adversaries with great naval superiority at a lower cost and personnel risk, lowering Russia’s asymmetrical advantage.[AB5] 

This emergent technology of sea drones has been further pioneered, with considerable success, by Ukraine against Russia's Black Sea Fleet. In first two weeks of February 2024, Ukraine claimed to have sunk the Russian corvette Ivanovits and a landing craft using inexpensive, domestically-produced ‘Magura V5’ naval drones.[15] While the UMS have not shown a 100 percent success rate, in that they apparently suffer from range limitations, the reward for striking high value warships provides an enormous asymmetric benefit.

Further south, Iranian-backed Houthi rebels, operating in areas of Yemen that they control, have been targeting international commercial vessels passing through the Red Sea in recent months. The multinational response to these hostile attacks includes Canada, which is providing 8 -10 staff officers. They are employed in intelligence operations, targeting, and command and control in Iraq, Jordan, and Lebanon, as well as supporting these southern Red Sea and the Gulf of Aden operations.[16]

The Houthi leadership claims that they are targeting ships with links to Israel in response to that country's ongoing conflict within Gaza, although most of the targeted ships have no apparent connection to Israel. In mid-February 2024, the US Navy reported engaging three anti-ship cruise missiles, “one unmanned underwater vessel, and one unmanned surface vessel.”[17] This was the first observed Houthi engagement by a UUV since attacks began in October 2023. The Houthis deployed both USVs and UUVs in a "swarm attack," which involved launching a number of relatively cheap missiles and drones simultaneously in the hopes of confusing and overwhelming their defences. RAdm Marc Miguez, the commander of the USS Eisenhower Carrier Strike Group, has stated that the sea drones were “more of an unknown threat that we don't have a lot of intel on, that could be extremely lethal," in that they present one of the more daunting scenarios, in having “ a bomb-laden, unmanned surface vessel that can go in pretty fast speeds. And if you're not immediately on scene, it can get ugly extremely quick."[18]

A UMV, surface or submerged, which has been designed for stealth, having only a limited surface profile, may be able to slip through even a well-watched area. Normal vessel traffic can obscure it, and even once it has been detected, the process of identifying it as a threat and authorizing the use of force may give it time to strike its target. As seen, swarms of UMVs could also be used, with a greater risk of early identification, but perhaps as the Houthi intended, also a high probability that at least some of them get through due to saturation of defences. These contemporary operations have brought forth a series of diverse concerns.

On 15 December 2016, a Chinese People's Liberation Army Navy (PLAN) ship, a Dalang-III class submarine rescue vessel, seized a US Navy UUV that was testing water conditions in the South China Sea about 50 nautical miles northwest of Subic Bay, Philippines in international waters and outside of China’s claimed territorial 9-Dash Line. The USNS Bowditch, (U.S. Pathfinder-class oceanographic survey vessel) with a mostly civilian crew, was in the process of recovering two unmanned ocean gliders, when the Chinese ship approached within about 500 metres of the Bowditch before dispatching a small boat, whose crew seized one of the gliders.[19]  The mere fact that China assigned this shadowing mission to a submarine retrieval ship is a strong indication that their intent all along was to steal an American UUV for examination before returning it, which they did, five days later on 20 December.

The Navy said the drones are operated by the U.S. Government’s Naval Oceanographic Office, which states in its promotional materials that it maintains the largest undersea glider fleet in the world, with more than 130 “littoral battlespace sensing” craft. The UUVs are used to collect information about water conditions that can help U.S. vessels operate, track China’s land reclamation efforts, or collect information about Chinese submarine routes.[20]

This seizure by the PLAN crew highlights the lack of agreement on the legal status of UMSs. If UMS are accepted as government or military ships, in accordance with the 1982 United Nations Convention on the Law of the Sea (UNCLOS) Articles 32, 58, 95, and 96, they should therefore have immunity from seizure.[21] Unfortunately, UNCLOS has no uniform definition of a ‘ship,’ although one of the assumptions is that, due to technical limitations when written, ships will have people on them. The UN definition of a warship does stipulate, in Article 29, that it be under command of an officer and managing a military disciplined crew. However, this is a moment that an expansive, evolutionary interpretation of the definition of a ship.[22] I see these UUV as fitting within the definition of warships and government operated ships.

While the most recent Defence Policy pledged to provide Canadians with regular updates on major project such as this. This government assurance has proven meaningless thus far, considering that both the European Union and the U.S. have provided greater transparency regarding the legal and policy framework for their use of autonomous vessels.”[23] Canada continues to fall disturbingly behind in the policy aspect.

For weapons to be consistent with International Humanitarian Law (IHL), they must conduct attacks with distinction, proportionality, and precaution, which most autonomous weapons currently lack. Further troubling, since Lethal Autonomous Weapons Systems (LAWS) behaviours evolve through artificial intelligence programs, it is impossible to know if LAWS will always follow distinction.[24] This evolution of ‘thought’ occurs because the operational algorithms include something called “machine intelligence,” which allows them to learn and adapt quickly and occasionally unpredictably. They may then acquire new capacities, select new targets, and assess different, more-effective modes of operating.[25]

Another concern highlighted by Center for a New American Security analyst, Paul Scharre, is that risks could arise from “hacking, enemy behavioral manipulation, unexpected interactions with the environment, or simple malfunctions or software errors,” which could potentially result in unintended and/or noncombatant casualties.[26] UMSs, particularly surface vessels, are also vulnerable to additional interference, such as by jamming, spoofing, or otherwise disrupting the data links between remotely piloted vessels and their operators. Any weaknesses in cybersecurity protection can compromise the data; it may be collected through theft, the data could be corrupted, or it may simply be deleted, rendering the craft unresponsive.

Discussions on autonomous systems have brought forth the term “meaningful human control,” wherein operators are making informed decisions about the weapons’ use. This requires three indispensable elements: both sufficient information to confirm the action’s lawfulness given knowledge of the target and the weapon; comprehension of the current conflict environment; and sufficient training to ensure effective and ethical control over the weapon.[27]

Meaningful human control is not, in fact, an additional requirement but rather a principle for the design and use of weapon systems in order to ensure that their use complies with the laws of war. This is necessary to ensure accountability, to avoid occurrences wherein a leader attempts to blame the weapon builder or delegating the killing of people to robots. Without human responsibility, there can be no justice when things inevitably go wrong in the fog of war.

Killer robots have been a staple of science fiction for several decades. Some look at AI as heralding the realization of murdering machines like “The Terminator” or the HAL 9000 computer turned villain in Stanley Kubrick's film "2001: A Space Odyssey." A United Nations’ report has stated that in March 2020, a LAWS autonomously hunted down and remotely engaged logistics convoys and retreating forces aligned with rebel General Khalifa Haftar in Libya. The conditions for the attack involved the drones’ prior destruction of the insurgent’s surface-to-air missile systems, leaving them vulnerable to the follow-on air attacks. While the veracity of the report is still being debated, if true, the concept of a “killer robot” will have moved from fantasy to reality.[28] Regardless, the bottom line is AI is not about killer robots running amok, it is about the efficient and successful use of vast quantities of information to solve problems in a timely manner.

Another concern is the growing apprehension regarding proliferation and misuse of UMSs. As noted, these vessels have undergone significant development over the last two decades due to technological advances, which has enabled an increased uncrewed presence in the maritime domain. This has been combined with a general reduction in the cost of systems and their components, thus increasing the possibility that these systems will be accessible to a larger number of actors —military and civilian, state and non-state. In parallel, there will be increased use of such systems for illicit activity, such as to aid with the transport of illegal goods. The ‘Pacific route,’ for example, sees the main ports of exit for drug trafficking out of Colombia, Peru, and Ecuador, direct to America, or to Mexican ports where they are subsequently transported to the US-Mexico border. Another armed nonstate threat is piracy.[29] With UMS range consistently increasing, the world’s two most prolific pirate grounds off of Africa’s Gulf of Guinea and the coast of Somalia are well within striking range of technologically-advanced pirates.

The use and proliferation of UMSs could also potentially change the threshold for the use of force. By lowering this threshold, and its definition within international law, it could incentivise armed hostilities or conflict.  Additionally, by removing personnel from the hazards of war, using UMSs could lead to an intensified maritime presence, with the risk of hostilities either intentionally or through miscalculation.

To conclude, it is inevitable that future vessels will be increasingly autonomous. Current research indicates UMS that will be progressively stealthier in addition to being able to cross domains, as amphibious craft designs advance. Innovation is being seen in power sourcing and propulsion as advances are made in hydrogen-oxygen fuel cells and other renewable power sources. As well, we are now seeing animal-inspired propulsion movement, which mimic cephalopods like squid or octopi.[30]

The U.S. Navy’s Chief of Naval Operations, Admiral Lisa Franchetti, has proclaimed that the Navy will operate a mixed “manned-unmanned fleet within the next decade or so, thanks to the prototyping and learning happening today.”[31]  Creating the requisite infrastructure, networks, and operating concepts has already begun. This is partially to address ongoing concerns that the Navy’s manned fleet is too small, currently sitting at 292 warships when there has been a stated requirement for more than 380. The U.S. Navy’s recent drive into UAVs such as the MQ-25A Stingray, UUVs such as Boeing’s Orca, and USVs such as the Large Unmanned Surface Vessel are clearly taking advantage of advances modern, long-range, secure communications. [32]

Canada currently faces a disconnect between the rapid advances in autonomous technology and the ponderous inertia of relevant legislation. Canada has committed to promoting international norms for the “appropriate responsible and lawful use of remotely piloted systems, in support of Global Affairs Canada.”[33] Sorting out the legalities will become increasingly critical for Canada as our arctic waters thaw, as this will draw increased maritime traffic -- crewed vessels and otherwise. Politics must catch up.

Before Canada deploys LAWS operationally, it must have in place clear policies governing precise and restrictive rules of engagement, to ensure strict adherence to International Humanitarian Law’s principles of distinction, proportionality, and precautions in attack. Further, Canada must be seen to be adhering to these principles, and otherwise complying with its obligations under international law.[34] Rather than looking towards America for guidance in this regard, whose track record in Afghanistan, Iraq, and Mali was referred to as “playing wack-a-mole,” the European Union’s efforts may prove more informative and in line with a Canadian philosophy.[35]

Established nation-states will not have a monopoly on this technology. Currently we see unspoken agreements in which there is no formal war featuring the kind of mass violence that would attract global attention. Conflicts have transformed from ‘to be resolved’ to ‘permanently managed.’ Transnational criminal networks are increasingly intertwined with political and business elites. Criminal violence is widespread in both managed democracies and patchwork states. In the near future, this will likely be the operating territory for autonomous vessels, as well as conventional military forces.[36]

Technological advances, especially in the field of AI, may motivate more and more countries, and non-state actors, into developing or acquiring and operating LAWS. This holds significant implications for political oversight and diplomatic treaties, military concepts of operations, and the future of warfare. As UMS develop, whether tethered to a controller or autonomously AI-driven, they will produce innovative tactics, increased flexibility, and —ultimately —a pawn to sacrifice for a queen.

Table 2: Acronyms

End Notes:

[1]Brett Samuels and Brad Dress, “Biden weighs high-stakes response to Iran after US troops killed in Jordan.” The Hill. 29 January 2024. https://thehill.com/homenews/administration/4436080-biden-iran-us-troops-killed-jordan.

[2] Armed Conflict Location & Event Data Project. “ACLED Factsheet | US strikes and counter-strikes in the Middle East (Updated 4 February 2024). Ameneh Mehvar, Middle East Regional Specialist. https://acleddata.com/2024/02/03/acled-factsheet-us-strikes-and-counter-strikes-in-the-middle-east (Accessed: 12 February 2024)

[3] United Nations Institute for Disarmament Research. Uncrewed Maritime Systems: A Primer. 19 October 2022. Theo Bajon and Sarah Grand-Clement. https://unidir.org/publication/uncrewed-maritime-systems-a-primer. (Accessed: 21 January 2024): 2.

[4] Canada, Department of National Defence, Strong, Secure, Engaged. Canada’s Defence Policy. 2017. https://www.canada.ca/content/dam/dnd-mdn/documents/reports/2018/strong-secure-engaged/canada-defence-policy-report.pdf

[5] UNDIR, Uncrewed Maritime Systems: 1.

[6] Thomas B. Sheridan, Humans and Automation: System Design and Research Issues. Hoboken, New Jersey: John Wiley & Sons, 2002.

[7] Anthony E. Sokol, “German Experiments with Remote Control During the Last War.” Proceedings. Vol. 70 no. 2, February 1944: 492.

[8] Ibid.: 496.

[9] RAND. U.S. Navy Employment Options for Unmanned Surface Vehicles (USVs). (1 November 2013). Scott Savitz, et al. https://www.rand.org/pubs/research_reports/RR384.html: 1.

[10] Levent Bahadir, “The Legal Status of Unmanned Maritime Vessels (UMVs) Used for Military Purposes.” Journal of Applied and Theoretical Social Sciences 5 no. 4 (December 2023): 400.

[11] Raul Pedroso, “Advent of a New Era in Naval Warfare: Autonomous and Unmanned Systems.” Autonomous Vessels in Maritime Affairs: Law and Governance Implications. Johansson, T.M., Fernández, J.E., Dalaklis, D., Pastra, A., Skinner, J.A. (eds). Palgrave Macmillan, Cham. March 2023: 67.

[12] Bahadir, “The Legal Status of Unmanned Maritime Vessels: 400.

[13] RAND Commentary, “Beware the Explosive Vessels.” (20 October 2022). Scott Savitz, Senior Engineer. https://www.rand.org/pubs/commentary/2022/10/beware-the-explosive-vessels.html. (Accessed 19 February 2024).

[14] Ibid. The principle is similar to the British Second World War Commando raid in which the HMS NAME was rammed into the St Nazaire ship repair facility, with the troops escaping before several tons of explosives detonated, incapacitating the drydock until after the war.

[15] Mia Jankowicz, “Sea drones are being used to smash Russia's navy, and now they're being used to threaten a US carrier strike group too.” Business Insider. 16 Feb 2024. https://www.businessinsider.com/us-warship-fighting-off-houthi-sea-drones-red-sea-ukraine-2024-2.

[16] Canada, DND, Strong, Secure, Engaged.

[17] U.S. Central Command. “Press Release: Feb. 17 Summary of Red Sea Activities.” Release Number 20240218 – 01. Tampa FL, 2024. https://www.centcom.mil/MEDIA/PRESS-RELEASES/Press-Release-View/Article/3680306/feb-17-summary-of-red-sea-activities (Accessed: 19 February 2024).

[18] Jankowicz, “Sea drones are being used to smash Russia's navy.”

[19] Missy Ryan and Dan Lamothe, “Pentagon: Chinese naval ship seized an unmanned U.S. underwater vehicle in South China Sea,” Washington Post. 17 December 2016. https://www.washingtonpost.com/news/checkpoint/wp/2016/12/16/defense-official-chinese-naval-ship-seized-an-unmanned-u-s-ocean-glider (Accessed 5 February 2024).

[20] Ibid.

[21] United Nations Convention on the Law of the Sea. 1982. https://www.un.org/depts/los/convention_agreements/texts/unclos/unclos_e.pdf (Accessed 5 August 2023): 31,40, 56,

[22] Simon McKenzie, “When is a ship a ship? Use by state armed forces of un-crewed maritime vehicles and the United Nations Convention on the Law of the Sea.” Melbourne Journal of International Law 21 no. 2 (December 2020): 12-13.

[23] Canada, DND, Strong, Secure, Engaged, 75, 112. Craig Martin, “What Role and Rules for Canada’s Armed Drones?” Canadian Global Affairs Institute, (December 2018): 2.

[24] Roser Rierra-Serra, “Toward Lawful Governance: Recommendations for the Safe Use of Autonomous Weapons.” (BA Paper, Bishop’s University, 2024): 5.

[25] Ibid.: 4.

[26] U.S. Congressional Research Service. “International Discussions Concerning Lethal Autonomous Weapon Systems.” IF11294, 14 Feb 2023. Kelley M. Sayler, Analyst in Advanced Technology and Global Security. https://crsreports.congress.gov/product/pdf/IF/IF11294: 2.

[27] Michael C. Horowitz and Paul Scharre, Meaningful Human Control in Weapon Systems: A Primer. Center for a New American Security. March 2001: 4, 11.

[28] United Nations, Security Council. Final report of the Panel of Experts on Libya established pursuant to Security Council resolution 1973 (2011). Lipika Majumdar Roy Choudhury, et al. New York: NY: UN Headquarters, 8 March 2021. https://documents.un.org/doc/undoc/gen/n21/037/72/pdf/n2103772.pdf.

[29] Kara Chadwick, “Unmanned maritime systems will shape the future of naval operations: Is international law ready?” Maritime Security and the Law of the Sea: help or Hinderance. Help or Hindrance? Ed. Sir Malcolm D. Evans. Northampton, Massachusetts, Edward Elgar Publishing: 140-145.

[30] Bajon and Grand-Clement, Uncrewed Maritime Systems: 5.

[31] Megan Eckstein, “Franchetti confident prototypes will usher in manned-unmanned fleet.” Defense News. 13 February 2024. https://www.defensenews.com/naval/2024/02/13/franchetti-confident-prototypes-will-usher-in-manned-unmanned-fleet.

[32] Kyle Mizokami. “The Surprising History of Unmanned Navy Systems.” Proceedings. June 2020 Vol. 146 no. 6, June 2020.

[33] Canada, DND, Strong, Secure, Engaged, 73.

[34] Martin, “What Role and Rules for Canada’s Armed Drones?”, 10.

[35] European Parliament Directorate-General for External Policies Policy Department, Towards an EU Common Position on the Use of Armed Drones, (2017). http://www.europarl.europa.eu/RegData/etudes/STUD/2017/578032/EXPO_STU(2017)578032_EN.pdf . The “wack-a-mole” comment comes from the author’s experience working the Combined Joint Special Operations Task Force in Afghanistan, reaffirmed by an unnamed Canadian staff officer in Mali, upon receipt of a threat assessment, in an email to author, November 2018. The Mali paper is available as, Robert Martyn, “Radicalization in Mali – A Primer,” Queen’s University Centre of International and Defence Policy, Policy Brief, Vol. 4, Issue 5 (Nov 2018).

[36] Sarah Bressan and Mari-Liis Sulg, “Welcome to the Grey Zone: Future war and peace.” New Perspectives, 1–19. http://www.academia.edu/67786656/The_Phenomenon_of_New_Wars_Changing_Nature_and_Violence_Diplomacy

[37] United States Naval Ships are unarmed auxiliary support vessels owned by the U.S. Navy and operated in non-commissioned service by Military Sealift Command with a civilian crew. They are not considered to be warships.