Maritime Security refers to constabulary functions such as protecting commerce from terrorists and pirates and preventing illegal behavior such as arms smuggling and drug running. In such operations, small and medium unmanned surface vessels could technically conduct surveillance, issue warnings, or engage threats with small-caliber weapons while under remote human control. The latter, however, seems especially unlikely in practice. Maritime security is a peacetime endeavor, conducted in congested sea space among civilians. Accordingly, there is a high premium on positive identification of bad actors, and generally the goal is not to kill anyone. A human touch will be required – not just “in the loop,” but probably on-scene.

Another problem is that, if unmanned vessels are small and cheap – two of their most celebrated characteristics – terrorists and drug runners may be able to disable them quite easily. Saildrone, therefore, adds most value for maritime security ISR under the following narrow set of conditions: when no aviation assets, satellite coverage, or allied coast guards are available; manned ships or shore facilities are within communications range; it is sunny, or enough sunny days have recently passed to keep batteries charged; and the targets of surveillance are incapable of shooting at, or (as with Iran in 2022), attempting to capture the drone monitoring them from within visual range.

The Risks of Concentration

Most contemporary Navy ships can be used for a variety of the missions delineated above. Destroyers can be used for power projection, sea control, presence, and maritime security; aircraft carriers can be used for all of those; amphibious assault ships are best for power projection and presence but can readily support maritime security. None of this is true for any unmanned vessel – not any in production, and none even in the design phase. A large unmanned surface vessel will have one purpose: to support power projection. Medium unmanned surface vessels will have two purposes: to contribute to sea control and maritime security.

Multi-mission capability, however, is not necessarily the goal. Unmanned assets, proponents argue, will not replace manned ships, but rather augment them as part of a “hybrid fleet.” The Navy expects a force structure that is 40 percent unmanned by 2050, although that does not mean that each naval mission area will be 40 percent unmanned. Some missions will rely more heavily on unmanned platforms than others will. This means the risks of unmanned vessels will not be evenly distributed across the Navy’s missions.

In general, we can forecast that unmanned vessels will fall out of operation (in peacetime) or attrite more quickly (in wartime) than manned ships for two reasons. First, the technology is immature and likely to remain so for a long time; currently, unmanned vessels are prone to inherent hull, mechanical, and electrical casualties, and cyber vulnerabilities. In brief, persistence is these vessels’ greatest challenge (and one the Defense Advanced Research Projects Agency is attempting to solve). Unmanned vessels may be required to keep station for weeks or months, in contrast to aerial drones’ persistence times, which are measured in hours. The longer unmanned surface vessels are at sea without maintenance, the greater their chance of routine equipment failure that either requires remote troubleshooting or on-scene repair. The former incurs both electromagnetic targeting and cyber risk. Second, unmanned vessels are explicitly designed to be less survivable, or “expendable” in the words of proponents.

The New York Times feature article mentioned previously illustrates the problem. It observes that the Navy has not scaled the success of Saildrone by integrating larger unmanned surface vessels into the fleet. This failure is attributable, the article argues, to bureaucratic inertia and industry capture. Missing from the discussion is the fact that the hull, mechanical, and electrical solutions required to field a 2000-ton medium unmanned surface vessel (especially one capable of persistent operations) are an order of magnitude more complex than those required for the 14-ton Saildrone. The propulsion requirements alone, let alone combat systems, place the former decades behind the latter in technological maturity. It is therefore nearly guaranteed that by 2030, for instance – even if the Navy has increased the overall percentage of unmanned vessels in its force structure – the Navy will not be able to have significant numbers of unmanned vessels in key mission areas.

Accordingly, the Navy must assess concentration risk: what happens when certain missions, but also warfare areas within those mission areas, degrade at different rates due to the differential survivability of manned versus unmanned assets. As a thought experiment, let us assume the Navy hits its 40 percent unmanned target. However, because Saildrones are far less technically complex, and far cheaper, than large unmanned surface vessels, the future fleet has more of the former than the latter. That future fleet would therefore be more reliant on unmanned assets for maritime security than for presence. Suppose, then, that China executes a successful cyber attack against a network of Saildrones; suddenly the maritime security mission is compromised, and the Navy must draw on its manned assets to support it – at the expense of the presence mission.

Sound unrealistic? Ukraine recently hacked Iranian-made drones used by Russia; during the Solar Winds hack, malicious code was delivered via legitimate code process; and the National Oceanic and Atmospheric Administration’s satellite network was hacked on at least one known occasion. And these are only some of the reasons why any unmanned asset with external communications capability must be assumed as cyber-vulnerable by default.

Beware Innovation for Innovation’s Sake

It should make the hairs stand up on the back of one’s neck when a new capability is described as simultaneously cheaper and more effective; when dozens of articles use the same buzzwords; when strategy documents are heavy on sweeping generalizations and light on detail; when the claim that technology will “mature” is delivered as a certainty; when “innovative” is treated as synonymous with “useful;” or when the same few empirical examples appear in every article on a subject. All of these are present in spades in media coverage of unmanned vessels.

If the U.S. Navy is to embark on a costly project with uncertain chances of success, it owes Congress and the American people a better Unmanned Campaign Framework, or an unclassified concept of operations that disaggregates the role of unmanned ships across the Navy’s various missions, and the warfare areas that comprise them. Such a concept must be honest about concentration risk and suggest ways to mitigate it. And Congress, which has already begun to take a deeper interest in unmanned platforms, should hold the Navy to account.

Jonathan Panter is a Ph.D. Candidate in Political Science at Columbia University. His dissertation examines the strategic logic of U.S. Navy forward presence. Prior to attending Columbia, he served as a Surface Warfare Officer in the U.S. Navy.

The author thanks Anand Jantzen and Ian Sundstrom for comments on an earlier draft of this article.

This article was first published by CIMSEC.

Image: DVIDS.