Amphibious Black: Guerrilla Warfighting in the Maritime Domain

Early last year during an at-sea training event, elements of 1st Battalion, 6th Marines, and SEAL Team 2 united with the USS Arlington (LPD-24) and Winston S. Churchill (DDG-81) to form an “Amphibious Black” maritime force to demonstrate two future concepts for the Navy and Marine Corps: distributed maritime operations and expeditionary advanced base operations (EABO). Amphibious Black is a form of maritime guerrilla warfare in which, after decades of fighting insurgencies across the globe, we become the guerrillas.

Operating away from concentrated task forces with strict emissions control (EmCon), we maneuver deep inside a peer adversary’s antiaccess/area-denial (A2/AD) weapons engagement zone and scatter groups of Marines across several islands and shorelines to harass and cripple sea lines of communication. We create so many targets—real or imagined—that the enemy cannot decide who to attack, forcing him to disperse or get sucked into naval ambushes.

Our four-unit Amphibious Black team—an amphibious warship, a destroyer, a company of Marine infantry, and two SEAL platoons—demonstrated that this capability is available now with the incorporation of land-based antiship weapons and a mission command philosophy. It also should inform senior leaders’ decisions regarding major investments in new platforms and other force-shaping measures, such as the Light Amphibious Warship and Marine littoral regiments. The Navy and Marine Corps need to start testing variations of Amphibious Black in all integrated exercises to hone our asymmetrical warfighting edge.

How Does Amphibious Black Work?

Amphibious Black blends blue (Navy), green (Marine Corps), and black (Naval Special Warfare [NSW]) forces with a two-ship surface action group (SAG) to establish expeditionary advanced bases in A2/AD environments.

Blue

The blue element in our event consisted of a San Antonio–class amphibious ship and an Arleigh Burke–class destroyer. The LPD can deliver elements of up to six small expeditionary advanced bases (EABs), as well as two high-speed landing craft, air cushion (LCACs), and various small boats. It also has a 209-foot flight deck capable of carrying two MV-22 Ospreys or four MH-53 helicopters for rapid air transport and logistics. In our exercise, we established one robust EAB with two LCACs and three MV-22s. However, for transport redundancy and the establishment of leaner, more distributed EABs, we recommend deploying each EAB with just three lift elements—that is, some combination of one or two LCACs and one or two helicopters or MV-22s.

The DDG adds multidomain afloat force protection and speed. It provides protection to the Amphibious Black team at all phases of deployment, with SM-2 and SM-6 missiles for air and surface attacks and Tactical Tomahawks and the 5-inch gun for land strike. Alternatively, the DDG can take advantage of its speed and push forward to support NSW activities in advance of EAB insertions. While the LPD has limited air-defense and antisubmarine capability, it carries a modern array of radars and contributes to the cooperative engagement capability network, enhancing the destroyer’s lethality for SAG defense.

However, there is room for improvement in the LPDs. In recent years, for example, the naval services have struggled with ways to up-gun the San Antonio–class warships.¹ In its present configuration, the LPD has space to support a vertical launch system, which potentially could support the SM-6 or some other antiship missile. Another option would be to add modular missile systems, which could be placed behind the pilothouse with minimal modification. Either way, these additional capabilities would enhance the sea-denial mission and assist with force protection for EABs ashore.

Green

Assuming the embarked Marine force has the primary role of sea denial, we envision two or three company-sized EAB hubs (approximately 180 Marines each), each dispersed across several subsites. Core missions would include command and control (C2) ashore, intelligence, integrated fires, and force protection. Just as important would be the ability to conduct theater security cooperation or foreign internal defense. The Marines also would need to cooperate with host populations for necessities such as food, water, power, and force protection. Several subelement EABs with antiship missiles, radar, and various intelligence, surveillance, and reconnaissance (ISR) platforms would endeavor to blend into the terrain. These forces would be capable of providing both collections and fire support to the theater naval component to challenge an adversary’s ability to maneuver in his own area of operations. Taken a step further, we envision frequent redeployments (or feints) from one location to another to enhance military deception.

The most efficient amphibious insertion of these forces would be a single-wave ship-to-shore, rather than loitering in a waterspace “box” for hours or committing LCACs and aircraft to multiple trips to the same location. To prevent the Marines from becoming refugees in 96 hours, battlefield contracting officers should be included to facilitate food, water, and power for life support.

Antiship missiles are key to the EABO sea-denial strategy. In our exercise, we inserted a High Mobility Artillery Rocket System (HIMARS) for one EAB, but we had the capacity to deliver several more. Medium- to long-range antiship missiles allow EABs to be an extension of the greater naval force inside the adversary’s A2/AD region, where both adversary warships and shipping traffic need to be held at risk. Indeed, the Marine Corps must continue to prioritize a blend of antiship capabilities, such as the Remotely Operated Ground Unit for Expeditionary Fires truck with the Naval Strike Missile and upgrades to the M142 HIMARS with Tomahawks or other capable missiles.²

Black

Naval Special Warfare is the third leg of Amphibious Black. Here we should consider the words of Marine Lieutenant Colonel Pete Ellis, who 20 years prior to World War II laid the groundwork for the successful amphibious campaign in the Pacific: “Small parties . . . might go ashore at night for the purpose of seizing positions preparatory to a landing in force, provided there is small chance of discovery.”³ We envision having to do this at multiple potential landing sites while operating in unfamiliar and contested waters in the lead up to major conflict.

In our exercise, we employed two platoons from SEAL Team 2 to assist with beach surveys to verify the suitability of landing sites and provide ISR beyond the beach. This is required prior to any amphibious landing, and even more so when conducting multiple disaggregated ship-to-shore movements across several islands. We must assume we will be landing sailors and Marines in potentially untested and contested areas without time to conduct beach surveys with conventional forces.

Additional missions for the black element include foreign internal defense; battlefield contracting to prepare for incoming EABs; countermine operations; contributions to feints; obstacle removal for LCAC entry; and sabotage of adversary equipment and communications. Indeed, NSW can return to its naval commando heritage while operating from warships and influencing events ashore.

As experienced in our exercise, the biggest challenge in incorporating black forces was the lack of experience in the conventional amphibious Navy working with NSW and other special forces elements. To contribute to a Pacific fight against a formidable adversary, NSW needs to be fully integrating with naval amphibious forces now. We recommend establishing a Marine Corps embarkation specialist billet at the NSW group level. These Marine officers are experts at amphibious ship loading and unloading, and their voices would accelerate Amphibious Black concepts. Further, we should leverage the Navy’s optimized fleet response plan training events to provide opportunities for blue/green/black teams to cooperate. We found the usual growing pains of throwing together disparate units with little prior preparation could be overcome with just one to two weeks of direct cooperation and rehearsal.

Challenges

Even with the most robust host-nation support, ammunition likely will not be able to be purchased locally, and we do not want to emulate Japanese strategy in the Pacific campaign and hang EABs out to dry. Therefore, the two-ship Amphibious Black SAG will need to operate on a continuous “insert-replenish-extract” cycle, while constantly moving. We envision several EABs being resupplied or repositioned near simultaneously in this cycle, and multiple pre-insertion NSW operations might be ongoing while one or two EABs are embedding at other locations. The SAG will be servicing them all—whether it is providing resupply by LCAC or vertical lift, extracting forces from one location and inserting them elsewhere, or rendezvousing with a Military Sealift Command ship for replenishment at sea.

Emissions control also is central to this tactic. We practiced this for several days, but only to a degree. EmCon is a challenge when connectivity must be maintained for exercise white cells, daily video teleconferences, and chats with fleet battle watch captains ashore. Our reliance on supporting theater C2 information requirements could in fact be our Achilles heel. This is where mission command comes in—the idea that we should anticipate the loss of C2 networks and communications and act on mission-type orders and conduct fully decentralized operations.⁴ That said, the naval services have not yet adopted this culture in practice. The only alternative is to incorporate highly survivable and redundant communication paths with very low probability of intercept. Even these will not be effective, however, if fleet commanders are operating out of fixed sites ashore, which are the least likely targets to survive a true contest of adversaries.

‘Firstest with the Mostest’

To quote the Chairman of the Joint Chiefs of Staff General Mark Milley, “If we don’t get there ‘firstest with the mostest,’ and we don’t put the pedal to the metal and do this right over the next 10 or 15 years, we are condemning a future generation to what happened 76 years ago” when Germany took most of Europe.⁵ The chairman was referring to a confluence of new technologies and associated training, but the same applies to Amphibious Black.  If we do not practice Amphibious Black now and start shattering adversary A2/AD efforts in every possible integrated exercise, we will hinder future generations.

We challenge leaders and exercise planners to experiment with longer-term, communications-denied scenarios; to execute creative SAG operations under mission command; and to implement a full sustainment cycle with multiple EABs. Align Navy and Marine Corps objectives for distributed maritime operations and EABO and demonstrate what we can do as maritime guerrillas.