Practice Notes: A Waterproof Guide to the Law of the Sea and the Law of Naval Operations

Practice Notes

A Waterproof Guide to the Law of the Sea and the Law of Naval Operations

By Colonel Susan McConnell and Lieutenant Colonel John C. Tramazzo

The U.S. Army’s primary mission is to “organize, train, and equip its forces to conduct . . . land combat.”1 However, no military Service can ignore the “interconnectedness of sea and land.”2 A majority of people on earth live on land masses near or surrounded by water.3 Further, recent incidents involving cutting undersea cables, which impact communications on land, and ground-based attacks on commercial vessels in the Red Sea highlight the domain overlap.4

Indeed, as Field Manual 3-0 reflects, the Army must be prepared to operate in a maritime environment.5 The maritime domain includes littoral regions where salt water and wind might impact operations on land. It also includes the Arctic region, where ice can render roadways, seaports, and airfields unusable. In a future armed conflict, Army forces may be required to conduct offensive operations under these conditions, and they may be required to defend against enemy amphibious assaults. In our view, Army commanders and staffs, including judge advocates (JAs), must grapple with the unique challenges associated with the sea. This includes understanding the law of the sea and the law of naval operations.

We had the pleasure of studying these issues at the U.S. Naval War College from August 2022 to June 2023.6 The U.S. Navy’s Senior Service College (i.e., the College of Naval Warfare) and Intermediate-Level Education Course (i.e., the College of Naval Command & Staff) are co-located at Naval Station Newport in Rhode Island. Senior officers from all six Services and approximately seventy nations attend the “senior course,” while officers in the grade of O-4 from all Services and approximately ninety nations attend the “junior course.” The core curriculum for each cohort includes military history, strategic theory, security decision-making, joint maritime operations (including operational maritime law), and leadership in the profession of arms.7

After a year of considering strategic, operational, and some tactical-level issues from a naval perspective, we compiled a list of materials and recommendations for Army JAs interested in learning more about the law of the sea and the law of naval operations and for those who may provide legal advice in support of multi-domain operations in the future.

U.S. Dep’t of Navy et al., NWP 1-14M, The Commander’s Handbook on the Law of Naval Operations 1-3 (Mar. 2022).

The Law of the Sea

The contemporary law of the sea proceeds from the three 1958 Geneva Conventions on the Law of the Sea.8 Those treaties left several critical issues (e.g., the width of “territorial seas”) unsettled. Thus, between 1973 and 1982, the United Nations (U.N.) convened a conference to update the 1958 treaties.9 The resulting U.N. Convention on the Law of the Sea (UNCLOS) came into effect in 1994 after ratification by the requisite sixty countries.10

UNCLOS is considered a constitution for the world’s oceans, including the airspace above and the seabed and subsoil below them. Although the United States has not ratified UNCLOS, it recognizes that most of the Convention’s provisions reflect customary international law (CIL) and are binding on all nations.11 The 2022 National Security Strategy includes a vow that the United States will “stand up for freedom of navigation and overflight, support environmental protection, and oppose destructive distant water fishing practices by upholding international laws and norms, including the customary international law rules in [UNCLOS].”12

UNCLOS and CIL govern military operations in the maritime domain, which includes “the oceans, seas, bays, estuaries, islands, coastal areas, seabeds, and littoral zones, including the airspace above these geographical areas.”13 UNCLOS and CIL also regulate maritime navigation, commerce, and the conservation, regulation, and exploitation of ocean resources.14 Understanding this body of law is critical considering ongoing disputes and malign behavior in vital locations like the South China Sea and the Persian Gulf.15 As some scholars have argued, “[T]he threat of naval war is growing.”16 Additionally, as the Arctic Ocean melts, the law of the sea will impact how states traverse newly navigable waterways and conduct or protect new commercial activity.17

To deepen their understanding of the law of the sea, we recommend that practitioners read the full text of UNCLOS,18 the 1983 U.S. Ocean Policy Statement,19 Senate Treaty Document 103-39,20 the 1989 USSR-U.S. Joint Statement with Attached Uniform Interpretation of Rules of International Law Governing Innocent Passage,21 and the U.S. Position on UNCLOS (prepared in 2021 by Professor Raul (Pete) Pedrozo for the Stockton Center’s International Law Studies).22 We also recommend A Practical Guide to the Law of the Sea by James P. Benoit,23 Tuft University’s internet-based policy primer on the law of the sea,24 and The Law of the Sea and Naval Operations, a straightforward law review article written in 1997 by Professors John Astley III and Michael N. Schmitt.25 These documents and resources are vital to understanding the laws applicable to the maritime domain.

The Law of Naval Operations

The Navy proclaims it will “fly, sail, and operate—safely and responsibly—wherever international law allows.”26 Many other nations’ navies do the same. Navigational freedom allows access to strategic areas of the world, facilitates support of deployed forces, enables military forces to operate worldwide, and ensures uninterrupted global commerce.27 However, this freedom is increasingly under threat. As the Chief of Naval Operations wrote in his 2021 Navigation Plan, “China and Russia are undermining the free and open conditions at sea that have benefited so many for so long.”28 The growing challenges that these nations and their actions bring to freedom of navigation have an outsized impact on U.S. maritime operations. Unlike land operations, which occur on states’ territory, only some naval operations occur in areas subject to the territorial sovereignty of states. Many naval operations occur in areas not subject to the territorial sovereignty of any state (i.e., international waters and international airspace). Military interactions in these global commons are ordinary occurrences for naval personnel, which is why an understanding of the law of naval operations is essential for them.

The law of naval operations includes those facets of international law, U.S. domestic law, U.S. military regulations, and the domestic law of other nations affecting military planning and operations at sea. During the deterrent or pre-hostilities phase of an operation, naval forces must respect the sovereignty of nations regarding their national airspace and territorial seas.29 During the hostilities phase of an operation, when the law of armed conflict (LOAC) governs the situation, the movement of military forces may be conducted without regard to the sovereign territorial rights of the enemy belligerent nation.30 However, the traditional sovereignty of other states (e.g., neutral states) must continue to be respected as a matter of law.31

To deepen an understanding of these foundational legal principles, we recommend that practitioners review the Second Geneva Convention,32 the 2023 Newport Manual on the Law of Naval Warfare,33 the Chief of Naval Operations’ 2024 Navigation Plan,34 the 2022 U.S. Indo-Pacific Strategy,35 Navy Warfare Publication 1-14M (The Commander’s Handbook on the Law of Naval Operations),36 the Newport Rules of Engagement Handbook37 (particularly its provisions on maritime operations), and the U.S. Freedom of Navigation Program.38

7th Special Forces Group performs an amphibious assault demonstration during the Hyundai Air and Sea Show and U.S. Army SaluteFest in Miami Beach, FL. (Credit: MSG Justin P. Morelli)

The Army’s Role in the Maritime Domain

Finally, as Field Manual 3-0 makes clear, “Army and joint force planning must reflect an understanding of the dynamic nature of the threats and constraints to land forces in maritime regions.”39 Army forces rely on maritime capabilities for deployment and sustainment.40 Maritime forces depend on the joint force for protection and to “secure geographic choke points,” “influence populations,” and “mitigate long timelines associated with maritime movement.”41

The Army is adapting its doctrine to integrate with the Navy’s “distributed maritime operations” concept, which relies on small, dispersed naval formations.42 Additionally, the Army must prepare to support the U.S. Marine Corps’s “expeditionary advanced base operations” (EABO) concept, which relies on “stand-in forces” in the littorals and the U.S. Air Force’s “agile combat employment” (ACE) concept.43 Army forces can enable maritime operations in multiple ways. Some of these ways include attacks against land-based threats to naval assets, protecting ports and defending land areas that control maritime choke points, denying maritime areas with surface-to-surface fires and surface-to-air fires, integrating joint all-source intelligence to identify threats to maritime capabilities, and providing directed logistics support to maritime-oriented forces operating from land. The Army’s multi-domain task forces, for example, are designed to support the sea Services with long-range fires and non-kinetic capabilities (e.g., electronic warfare support, cyber and space operations).44

JAs supporting multi-domain operations must be prepared to advise on issues relating to expeditionary basing and operational contracting; information operations; strikes against maritime targets; rules applicable to stopping, boarding, and searching vessels; rules applicable to the treatment of shipwrecked persons; support to displaced civilians; and command authorities (rules of engagement, collective self-defense, detention operations, etc.). By articulating the legal bases for operations, JAs can enable warfighting commands and counter adversaries’ incorrect claims that U.S. forces act in violation of international law. The legitimacy of U.S. operations is tied to international law and the narratives around it.

We recommend that Army JAs familiarize themselves with Joint Publication 3-32 (Joint Maritime Operations),45 Army Field Manual 3-0’s provisions relating to the maritime domain, particularly chapter 7 (Army Operations in Maritime Environments),46 and other Services’ multi-domain operating concepts.47

Conclusion

The United States is a maritime power that relies on the sea for food, security, projecting power, and facilitating economic prosperity. The oceans connect societies and businesses and create opportunities for cooperation, even with strategic competitors. The U.S. military plays a vital role in defending our Nation’s access to the sea by ensuring the openness of these massive global commons. Army forces are rapidly posturing to enable operations in the maritime domain, particularly in the Indo-Pacific theater, where China seeks to degrade U.S. influence and impede its freedom of movement. Army JAs must also prepare to enable multi-domain operations across the competition continuum. An understanding of the law of the sea and the law of naval operations is vital in this “decisive decade.”48 TAL

COL McConnell is the Staff Judge Advocate for XVIII Airborne Corps at Fort Bragg, North Carolina.

LTC Tramazzo is the Deputy Staff Judge Advocate for 1st Cavalry Division at Fort Cavazos, Texas.