Freedom of navigation operations: A mission for unmanned systems

Freedom of navigation operations: A mission for unmanned systems

By properly executing a transition to unmanned system freedom of navigation operation (FONOPs), the United States can use technological advances to ensure a continuing ability to “provide a legal order that will, among other things, facilitate peaceful international uses of the oceans.” Properly leveraged, unmanned systems will execute this mission at a significant cost savings, with a reduction in risk, and at a scale needed in a twenty-first century defined by great-power competition, writes Trevor Prouty in a recent piece in War on the Rocks

Trevor Prouty is an active-duty Navy commander who is currently the Navy Fellow at the Security Studies Program.​ He has served in three helicopter aviation tours, most recently leading a squadron during the adoption of the MQ-8B Fire Scout, an unmanned helicopter system.

US Navy vessel
Trevor Prouty
July 2, 2021

At first glance, the freedom of navigation operation (FONOP) conducted in the summer of 2023 mirrored previous US actions taken to contest excessive maritime claims in the South China Sea. A USNavy vessel sailed within twelve miles of Mischief Reef while conducting routine training maneuvers. However, in a departure from previous operations, the ship did not engage in man overboard drills as part of that training. It would have been odd to do so, since there were no humans aboard the vessel.

As this vignette suggests, the time has come for the US Navy to pass the freedom of navigation mission set to unmanned systems. This shift would provide significant benefits, including substantial cost savings, a reduced risk to human life, increased flexibility in escalation dynamics, and an asymmetric answer to geographically advantaged peer competitors in distant oceans.

Moreover, using unmanned systems for FONOPs could help to establish the desired US government precedent regarding these platforms and the law of the sea. The US Navy’s proactive demonstration of unmanned system operation across the globe could clearly communicate expected norms regarding their usage under existing conventions and customary law. 

A FONOPs Primer 

In order to understand the future of FONOPs within the context of unmanned systems, one should first examine the genesis of the US Navy’s freedom of navigation program, as well as the successes and challenges attributed to it by observers throughout its forty years of existence.   

The UN Convention on the Law of the Sea codifies customary international legal concepts pertinent to maritime claims. As President Ronald Reagan outlined in his 1983 speech on oceans policy, the United States “will exercise and assert its navigation and overflight rights and freedoms on a worldwide basis in a manner that is consistent with the balance of interests reflected in the convention.”

Despite substantial commercial and government support for the convention, the US Senate has not joined over 160 other countries in ratifying the 1982 law of the sea agreement. Initially, American opponents of ratification feared that the convention’s provisions for the governance of deep-seabed mining would run counter to domestic interests. More recently, concerns including sovereignty issuesand environmental restrictions have prevented the necessary Senate ratification vote from occurring. Both Presidents George W. Bush and Barack Obama pushed aggressively for ratification, yet failed due to political opposition. And while the current administration has largely remained quiet on any renewed efforts, in 2007 then-Senator Joe Biden led an unsuccessful attempt to move forward with ratification as the chairman of the Senate Committee on Foreign Relations.

Even without congressional ratification of the convention, legal experts cite enduring maritime law traditions that can create widely accepted customary rules without a specific requirement for binding international agreements. Based on this fundamental concept of customary international law, over the last four decades the US freedom of navigation program has combined diplomatic efforts with at-sea operations across the globe, sailing or flying through excessive maritime claims to reinforce the American interpretation of customary maritime claims.

Through these operations, the US government contests claims — against allies and antagonists alike — with a military presence in the disputed zone. Each year, a number of these excessive claims are contested. In Fiscal Year 2020, for instance, the Department of Defense challenged 28 separate excessive claims made by 19 different countries. Each challenge can represent a larger tempo of operations, as one listed maritime challenge may include multiple passages by US assets throughout the year.

Proponents of FONOPs assert that the program deserves credit for the freedom of the global commons enjoyed by maritime shipping today, the continued expansion of global sea trade over the last forty years, and a normalization of maritime claims in line with convention standards. The 2016 Chinese refusal to recognize the arbitral tribunal’s decision regarding disputes in the South China Sea bolsters the case for US FONOPs, highlighting the difficulty in enforcing the convention through purely diplomatic efforts at the international level.

FONOPs detractors, meanwhile, perceive the program as unnecessarily offensive in nature, emphasize the persistent threat of collision at sea with resulting escalation concerns, and question whether any behavioral changes can actually be attributed to military contestations.

Activity under the freedom of navigation program, which is approved and directed at the presidential level, has largely remained steady during recent administrations. This trend implies that American leadership values the program and supports the conclusion that FONOPs will remain a vital and visible part of US national security policy going forward.

The Advantages of Unmanned Systems During FONOPs

While forty years have elapsed since FONOPs’ inception, the tools used to execute the mission in 2021 still resemble those used in 1981. Twenty-first century unmanned systems technology offers opportunities to mitigate past weaknesses and amplify current strengths. By saving money and reducing risk while providing a response to rapidly expanding adversarial fleets, the US Navy can leverage unmanned FONOPs to breathe new life into the program during a vital period in its existence.

An Efficient Use of Assets

The Department of Defense can realize significant and much-needed cost savings by using unmanned platforms for the freedom of navigation mission set. The state-of-the-art Arleigh Burke Flight III destroyer, a likely candidate for completing FONOPs in the twenty-first century, has an estimated unit cost of $1.8 billion versus approximately $35 million for a medium-sized unmanned system prototype. Beyond the reduced initial investment, experts estimate daily operating costs for the manned destroyer at $700,000 versus a $20,000 daily price tag for unmanned surface systems, such as the Sea Hunter. In a time of flat-line Department of Defense budgets and a stated Department of the Navy desire to focus further on unmanned systems, employing drone technology for these operations provides clear cost advantages while aligning with modernization efforts.

Besides monetary savings, the use of unmanned systems for these missions allows more-capable manned platforms to focus on those tasks that require different competences or a human touch. FONOPs fall neatly into the category of “dull, dirty, and dangerous” operations that best fit unmanned systems. An unmanned system can easily refute a challenged nation’s excessive maritime claim that requires prior permission for innocent transit by conducting an unannounced straight-line passage through disputed waters, freeing a manned vessel and its crew to conduct more in-depth operations elsewhere.

Robots Can Reduce Risk While Providing Flexibility

In the event of a miscalculation on either side during an unplanned encounter at sea involving unmanned assets, metal and electronics may incur damage, but no human life will be lost. As recent non-FONOP ship collisions have shown, when two large-tonnage vessels collide at sea, a tragic loss of life may result. By removing the potential for this loss of life from a collision in contested waters, the use of unmanned systems during FONOPs allows technology to accomplish a potentially dangerous mission with no requirement for physical human presence.

Beyond the inherent heartbreak involved, the loss of human life also has implications for escalation. A recent study examined the different emotions generated from the loss of an unmanned system versus a manned system, and its findings demonstrate de-escalation advantages from an unmanned loss. In simple terms, the destruction of an unmanned system does not generate the same visceral and escalatory response as the loss of a human life. This vital difference adds flexibility following a collision at sea or a hostile act during FONOPs. While unmanned systems do not negate the potential for an escalation spiral, their use provides de-escalation options to decision-makers that do not exist with manned platforms. As geopolitical tensions continue to grow, opportunities to decrease potential escalation spirals stemming from collisions during FONOPs should not be ignored.

An Asymmetric Response to Being Outnumbered

Much attention in recent years has focused on the impressive scope of Chinese shipbuilding capabilities. In the waters of the South China Sea, the US Navy already finds itself outnumbered — even more significantly so when one includes the tremendous size and coercive capabilities of the Chinese maritime militia. According to the 2020 annual Department of Defense report to Congress, China has built the largest navy in the world, comprising 350 ships compared to the US Navy’s 293 ships. This disparity exists primarily in smaller hull classes, and further emphasizes the benefit of using lower-cost unmanned systems to even the numerical playing field. The maxim that “quantity has a quality all its own” will likely hold true in a dynamic twenty-first century battlespace. As recent budget submissions demonstrate, the US Navy simply does not have the necessary capital to match adversary numbers at traditional major surface combatant shipbuilding costs.

Low-cost unmanned systems will facilitate the dispersion of the naval assets necessary to ensure the successful conduct of peacetime FONOPs, while also enabling the execution of the distributed maritime operations wartime concept. The deployment of unmanned systems to counter current asymmetry creates an achievable and efficient option to execute assigned missions, such as FONOPs, while countering increasing naval proliferation across the globe.

Concerns Addressed

The near-term extensive use of unmanned systems during FONOPs necessitates both prudent planning and measured operational execution. The US government should establish a favorable precedent for the legal status of unmanned systems under existing conventions and enforce suitable repercussions for external interference with unmanned systems operating in accordance with customary international law.

Setting a Precedent

There is debate in legal circles over whether unmanned systems qualify as warships — a classification advantageous to the execution of freedom of navigation missions. Unfortunately, any comprehensive solution to this complex question will likely suffer due to the frayed relationships in today’s global environment, which make consensus difficult.

With this obstacle in mind, the best path forward for ensuring unmanned systems’ ability to conduct operations in accordance with accepted standards is through clear communication of intent and routine usage across the globe. Just as the US government has relied on its interpretation of conventionprovisions to dictate its actions around the world and reinforce customary international law, a transparent and publicly accessible US policy on unmanned system use on the seas could combine with at-sea operations to provide the necessary foundation for global acceptance. 

Signaling Resolve During Unmanned FONOPs 

Important questions also remain as to whether challenged nations will treat unmanned systems in accordance with the norms afforded to manned systems during FONOPs. Numerous instances already exist of nations capturing or destroying unmanned systems, including the shooting down of a US Navy surveillance drone by Iran in 2019. In that case, media reporting indicated that Iranian forces specifically chose their target based on its unmanned nature in an attempt to avoid further escalation. If an adversary believes they can target unmanned systems without any retribution, effective unmanned system usage across all mission sets will suffer.

With that consideration in mind, clear policy guidance prior to the execution of unmanned system FONOPs can signal the resolve and set the expectations necessary to ensure successful operations. The US government should credibly and consistently communicate that any actions taken to inhibit the navigation of these systems will be met with determination. Signaling could be accomplished via pre-negotiated international agreements or clear warning statements disseminated via the appropriate forum.

By credibly signaling resolve with respect to the execution of unmanned FONOPs, the US government could provide escalation expectations and manage risk effectively. The same escalation options available for the loss of a manned asset would be available for the loss of an unmanned asset, but with additional and less-escalatory rungs to climb along the way. These additional escalation steps include using manned assets to accomplish the mission, or a proportional military response when merited. In practice, certain — and likely most — circumstances will lend themselves to unmanned systems usage while rare situations may require more traditional means of contestation.

Preventing Technology Loss

Another commonly mentioned concern is the potential loss of technology resulting from the loss of unmanned systems. In this scenario, an unmanned system taken “captive” by a rival nation results in the loss of sensitive technology or information. This drama has already played out in real time, as witnessed by the capture of a US Navy oceanographic survey glider in 2016 and subsequent Chinese technological advances.

Before condemning unmanned systems for this fault, however, one should note that this problem is not unique to them. The 2001 emergency landing of a manned US Navy EP-3 in Hainan, China, resulted in the loss of sensitive materials. Going back further, the capture of the USS Pueblo and its crew in 1968 by North Korean forces also infamously compromised classified information and hardware, including ten encryption machines and thousands of pages of top secret documents.

Notably, unmanned systems may experience a higher likelihood of attempted tampering or interference than traditional assets due to the same traits that contribute to their de-escalation advantages. Ensuring the protection of sensitive information lies not in eschewing the use of unmanned systems, but rather in ensuring fail-safe methods for destroying relevant data when in danger of exploitation. As with their manned counterparts, unmanned systems operations should be approached from a continuing perspective of potential exposure with mitigations in place to avoid technological theft.

While manned systems can resort to a human and an axe in attempts to destroy equipment, unmanned systems’ hardware needs to automatically revert to a zeroized, or unusable, state in case of distress. Initiation of this process can be triggered by a command from its home station, the shock from a significant collision, or an extended loss of communication with its handler, inhibiting the loss of critically sensitive information and exploitation of the hardware itself.

Perhaps unexpectedly, unmanned systems possess at least one advantage in this realm. Unmanned systems negate the adversary’s ability to leverage human crews for nefarious purposes, such as the creation of damaging propaganda or the receipt of additional sensitive information via interrogation.

Unmanned Systems as the Platform of Choice for FONOPs

By properly executing a transition to unmanned system FONOPs, the United States can use technological advances to ensure a continuing ability to “provide a legal order that will, among other things, facilitate peaceful international uses of the oceans.” Properly leveraged, unmanned systems will execute this mission at a significant cost savings, with a reduction in risk, and at a scale needed in a twenty-first century defined by great-power competition.

Trevor Prouty is an active-duty Navy commander with more than 20 years of service. He is currently the Navy Fellow assigned to the Massachusetts Institute of Technology Security Studies Program.​ He has served in three helicopter aviation tours, most recently leading a squadron during the adoption of the MQ-8B Fire Scout, an unmanned helicopter system.