Maritime Hybrid Warfare Is Coming

By Admiral James Stavridis, U.S. Navy (Retired)

On a summer’s evening in the sweltering South China Sea, a coastal steamer of nearly 2,000 tons approaches a Vietnamese fishing fleet in the exclusive economic zone of Vietnam, some 150 miles off that nation’s coast. The steamer loiters in the area for an hour or two as night falls. Suddenly from the side of the ship three fast speedboats are deployed, each armed with .50 caliber guns and hand-held rocket launchers. For the next hour, the speedboats attack dozens of fishing craft, spraying them with .50 caliber fire, hitting them with grenades, and shooting at survivors in the water. The surviving fishing boats flee toward the coast, frantically radioing distress calls, which are jammed by small drones operating overhead.

By the time the Vietnamese Coast Guard arrives on scene the next morning, alerted by one of the boats that finally managed to limp into port, there is only blood in the water, mixed with oil and gasoline, and several smoldering hulls. One of the Coast Guard ships strikes a small, crude mine and sustains damage to its hull. On one of the still floating fishing craft, an improvised explosive device goes off when Vietnamese sailors board it searching for clues to the origin of the incident. Vietnamese social networks are flooded with warnings to fishermen that the waters of their traditional fishing grounds are full of terrorists. A series of cyber attacks cripples the Vietnamese offshore radar surveillance system.

China insists its armed forces were not involved and says it suspects gangsters running a protection racket, pirates, or domestic Vietnamese terrorists. Using both social networks and official channels, the Chinese immediately offer to provide protection against further attacks, pointing out that Vietnam appears unable to control its claimed waters and asserting the need to do so itself to safeguard Chinese vessels operating nearby. Similar social network campaigns occur throughout the nations around the western rim of the South China Sea. China uses the opportunity to reassert its claims of sovereignty over the entire South China Sea. Over the next several months, similar attacks occur on a variety of offshore vessels, oil platforms, and natural gas terminals.

Despite protests from a variety of nations around the littoral of the South China Sea, a threat of investigation by the United Nation’s International Maritime Organization, and stern words from the United States, a sense of chaos and instability develops across the most congested shipping channels in the world.

Much has been written about the emergence of “hybrid warfare” in a variety of global scenarios, notably in the Russian invasion of Ukraine and annexation of Crimea. To date, this largely has been confined to land warfare, in terms of both actual practice and theoretical discussion. That is about to change, and we will see the emergence of maritime hybrid warfare over the coming decades, perhaps sooner. Now is the time for the U.S. Navy to begin thinking about these scenarios and how to counter them, both for our own forces and on behalf of allies, partners, and friends in the global maritime coalition.

Hybrid Warfare Today

While views differ, the broadly agreed tenets of hybrid warfare ashore include:

• Creation of real strategic effect at the tactical level (sometimes called impact of the “strategic corporal”)

• Use of “soldiers” in unmarked uniforms (sometimes referred to as “little green men”), making their actions ambiguous under international law

• Elevated use of information warfare, propaganda, and the spreading of false and highly inflammatory rumors to destabilize a region

• Heavy presence on social networks generating propaganda and lies

• Special operators acting across the entire spectrum of violence

• Use of insurgent techniques—including car bombs, torture, and kidnapping—to frighten the population

• Incorporation of nonmilitary forces—including police and carabineer—into military operations

• A sophisticated cyber campaign

This witch’s brew of activity has proved effective in a variety of scenarios in so-called gray zones of conflict.

The fundamental idea of hybrid warfare is to find the space short of clear-cut military action with direct and recognizable tactical, operational, and strategic impact and compress it into a zone wherein sufficient ambiguity is created to allow an offensive actor a better chance of accomplishing an objective without full-blown, overt offensive action. In addition to Russia’s actions in Crimea and Ukraine, these techniques are being used by Iran in a variety of scenarios around the near Middle East, including in Syria, Lebanon, and Yemen. North Korea has used this approach against South Korea at sea. In addition, nonstate actors, including the so-called Islamic State, are beginning to mimic these activities ashore in more deliberate strategic ways. It also is conceivable that other transnational actors such as al Qaeda, Boko Haram, al Shabab, and other insurgent groups may develop hybrid capabilities to deploy in their regional campaigns.

So far, these ideas have been focused on land-based operations, but we are beginning to see them spreading into the maritime sphere. Perhaps most notably, Chinese activities in the South China Sea and Iranian actions in the Arabian Gulf are starting to show characteristics of hybrid war. This is a worrisome trend, as it has the potential to negate or ameliorate high-end U.S. nautical capability. The United States must start to consider its responses to hybrid warfare at sea, which may require developing new tactics and technologies, working closely with allies and partners, and building U.S. hybrid capability to counter its deployment by other nations and eventually transnational actors.

In addition, the United States should be considering the role of naval forces—Navy, Marine Corps, Coast Guard, and even Merchant Marine—in helping counter hybrid attacks ashore. Many of the capabilities developed to conduct and counter hybrid warfare at sea could be employed in the littoral, coastal regions, and eventually deep inland. This might be called “hybrid warfare from the sea,” and certainly is a potential part of maritime hybrid warfare.

What Is Maritime Hybrid Warfare?

Given its need to appear somewhat ambiguous to outside observers, maritime hybrid warfare generally will be conducted in the coastal waters of the littorals. Instead of using force directly from identifiable “gray hull” navy platforms, hybrid warfare will feature the use of both civilian vessels (tramp steamers, large fishing vessels, light coastal tankers, small fast craft, and even “low slow” skiffs with outboard engines). It also will be conducted and likely command-and-controlled from so-called white hulls assigned to the coast guards of given nations. Both the Chinese and the Iranians are using their coast guards (and revolutionary guards in the case of Iran) in this fashion in the South China Sea and Arabian Gulf, respectively.

The vessels being used for maritime hybrid warfare will be manned by a collection of what might be termed “little blue sailors,” individuals who are not exactly uniformed personnel. To give the appearance of non-state action, they may be categorized as nationalists, rogue actors, terrorists, or even “vacationing” sailors acting on their own volition. This technique was harnessed very capably by Russia during the invasions of Ukraine and the subsequent annexation of Crimea and allowed the Kremlin to spend weeks denying there were any Russian “troops” present on Ukrainian soil. The little blue sailors will not have any markings on their clothing, will not carry passports, and, if captured, will deny being part of any organized military.

On board maritime hybrid warfare platforms, a variety of weapons will be available, from light arms to heavier caliber but temporarily mounted machine guns, hand-held surface-to-surface missiles, and light surface-to-air missiles. The sailors also will have access to high-intensity laser dazzlers, sound emitters, tear gas dispensers, water cannons, and other nonlethal weapons. Their command and control will be compact, civilianized, and largely composed of off-the-shelf systems, but it will have the ability to deploy overhead, unmanned sensors (light, smart, cheap, and disposable). Over time, they will have the ability to deploy sonobuoys and underwater and surface unmanned sensors and to emplace permanent sensor nodes on the seabed. All this technology will be maintained ashore by special forces assigned in units to a nation’s coast guard and irregular maritime force.

At the most sophisticated level, it is conceivable a nation could build a small force of “Q Ships,” specially designed to look like coastal steamers or other small-to-mid size commercial vessels but that have concealed ports built into their sides for weapons, can launch speedboats from internal bays, and can function as mother ships for even smaller and less sophisticated vessels conducting maritime hybrid warfare. Such vessels also could surreptitiously discharge mines made in a crude and untraceable fashion to approximate maritime improvised explosive devices.

A particularly concerning element of maritime hybrid warfare could be attacks against offshore oil and gas installations. The ability to gravely damage or even destroy huge hydrocarbon installations in the Arabian Gulf, for example, without attribution could be an enormous advantage for Iran. Likewise North Korea could attack South Korean shipping terminals or pipelines. Underwater cables are likewise at risk, and eventually deep seabed mining rigs. This could have a chilling effect on further investment in a country or a region given the liability of environmental effects.

Nations also will think more coherently about how to use maritime forces to support hybrid operations ashore. Russia did so in a limited fashion in the Ukrainian conflict, and there are other scenarios in which such activity could be useful to a nation wishing to operated in the gray zone—say Iran against Gulf partners of the United States, North Korea against South Korea or Japan, or China in the South or East China Sea. This type of operation could consist of unmarked vessels, perhaps appearing to be fishing craft or even mixed in with legitimate fishermen, to provide surveillance, logistics, command and control, or shore fires against an antagonist. In addition, it would afford the means to attack inland installations from the sea in support of operations ashore. This is similar to traditional sea basing operations (such as were used in the initial invasion of Afghanistan in 2001-2002), except it would be done from unmarked vessels to prevent attribution.

The big advantages of maritime hybrid warfare are fourfold:

• First, it allows a nation to conduct operations to intimidate, degrade, and destroy an opponent’s capabilities without certain attribution. This allows greater latitude of activity as it avoids criticism and sanctions from the international community.

• Second, maritime hybrid warfare bestows the advantage of surprise, as a recipient may not suspect the punch that is about to land.

• Third, its techniques give the user effective control of the tempo and timeline of events, given their inherent ambiguity.

• Fourth, it is much less expensive than building the massive and capital expensive platforms needed to conduct conventional littoral warfare.

There is coming an age of maritime hybrid warfare, and the United States needs to prepare for it.

What Should the United States Do?

Build Intellectual Capital. The most important thing we can do today is to study, analyze, and fully understand how the ideas of hybrid warfare as practiced today will both translate to the maritime sphere and develop there in lethal ways. This means not only looking closely at current practice by Russia, China, North Korea, and Iran, but also having our own strategists and tacticians focused on this possibility. The Naval War College should take the lead on analyzing this phenomena, working with the various community tactical centers. This also is a rich area for collaboration with other service war colleges, notably the Army War College, which is studying hybrid warfare extensively in the land-based context.

Develop Tactical and Technological Counters. As we grow to appreciate the ability of an opponent to deploy this kind of warfare, we need to think coherently about what capabilities and tactics we already have that can counter it. There has been significant work done to counter Iranian small boats in the Arabian Gulf (although the Iranians’ capture of a pair of U.S. Navy riverine boats hardly imparts confidence in what we have generated so far). We need to adapt that riverine and coastal work into thinking about higher levels of maritime hybrid warfare directed against us.

Similarly, we have some technologies that will be helpful. The essence of defeating this kind of approach is shining a light on it through intelligence and information sharing to deny an adversary the ambiguity he seeks. This can be done in part by linking international partners, the interagency and intelligence communities, and even private-sector elements to observe and record activities. In addition, finding or honing technological counters for the techniques and procedures described above—from crude mines to armed speedboats to cyber and psychological attacks—can be assigned to the material commands.

Work with Coalition Partners. Many of the potential targets of maritime hybrid warfare are staunch partners of the United States—Japan, South Korea, the Kingdom of Saudi Arabia, Bahrain, Qatar, and the United Arab Emirates. Others are partners or friends, including Vietnam, the Philippines, and Malaysia. Using forums such as the International Sea Power Symposium or the coast guard counterpart, we should encourage cross talk, exchange best practices, and share intelligence on this emerging concern. Many of our partners, particularly in NATO, have exceptionally capable coast guards. Some have given thought to these types of problems, and more of them are showing enthusiasm about doing so.

Train and Exercise against Maritime Hybrid Warfare. We need to begin to practice countering these types of operations. This can be done as part of the basic cycle of work-ups for the surface Navy. Both submarines and aviation have a role to play as well. The ambiguity of these scenarios will require education and training in rules of engagement, operating our conventional systems against unconventional forces at sea, and learning to act more like a network at sea in the littoral. We have come a long way in counterterrorism thinking building on the concepts from Deep Blue—an operations group created in 2001 to come up with innovative ideas on how to tackle the war on terrorism—about the need to fight a network with a network; much of that thinking can be built into our training and exercise programs. Big international exercises such as Rim of the Pacific (RIMPAC) could include such scenarios.

Leverage the U.S. Coast Guard. Within the Sea Services, these challenges are an obvious zone of excellence for our unmatched U.S. Coast Guard. Involving it in a leadership role in combating maritime hybrid warfare is crucial. Many of its systems and platforms already contain the technologies to counter maritime hybrid warfare techniques, and its ethos and fighting spirit applied in this tactical arena would be powerful. In particular, the Coast Guard could be the nexus of a global maritime coalition approach that brings coast guards and coastal forces together to train. Fortunately, some of this already is being considered by the U.S. Coast Guard both unilaterally and with partners in the context of counternarcotics, counter­piracy, and counterterrorism operations at sea. What remains is to think through how to leverage it against a much more sophisticated, national-level opponent.


Hybrid warfare is as old as combat itself. There is nothing fundamentally new about incorporating unconventional, and unacknowledged, forces on the battlefield in surprising ways to undermine conventional forces and obscure attribution. But what is changing is the level of effort put into it by both big and small nations and the tendency to use it for all the tactical and strategic advantages it confers. Inevitably, it will sail out to sea and prove a formidable challenge if we have not thought through its uses and how to counter it. Let’s get under way.

Admiral Stavridis served for seven years as a four-star admiral, including nearly four years as the first Navy officer chosen to be Supreme Allied Commander of NATO. He currently is dean of the Fletcher School of Law and Diplomacy at Tufts University.



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