After HMS Conqueror sent the Argentinian cruiser General Belgrano and 323 Argentine sailors to their final resting place on 2 May 1982, the remainder of Argentina’s fleet retreated to home waters—all except the submarine San Luis. Argentina hoped this lone diesel boat, marginally functional and half-crewed, could avenge the General Belgrano and turn the tide of the war by sinking a British aircraft carrier.1
Admiral Sandy Woodward, commander of the Royal Navy’s task force during the Falklands War, keenly appreciated this threat: Losing either of his two carriers could lose the war for Britain. In response, Woodward deployed 11 destroyers, 5 nuclear submarines, 1 diesel submarine, and 25 helicopters in the most intense submarine hunt in modern history, expending 6,847 flight hours and 50 lightweight torpedoes in a failed attempt to sink the San Luis.2 Still, the submarine eventually made three ineffective attacks, including one against a British carrier, before withdrawing because of mechanical failures.3
The Falklands campaign revalidated Soviet Fleet Admiral Sergey Gorshkov’s observation that antisubmarine warfare (ASW) requires large numbers of ships and aircraft to counter each enemy submarine. He noted the Allies deployed 25 ships and 100 aircraft for each German submarine they faced during World War II.4 While ASW technology has improved since the Falklands War, submarines have become stealthier, more widely proliferated, and better armed. Today, ASW continues to demand disproportionate resources.
But, despite a more challenging ASW environment, the U.S. Navy fields proportionally fewer dedicated ASW platforms than it did in World War II or the Cold War. Modern ASW tools have greater capability, but there are not enough to protect a global fleet against dozens of hostile submarines. Consequently, scarce ASW platforms need to be optimally placed, well-protected, and well-supported to be effective. Marine Corps Commandant General David H. Berger has advocated in broad terms for Marines in expeditionary advanced bases (EABs) to support future ASW operations, writing: “The undersea fight will be so critical in the High North and the western Pacific that the Marine Corps must be part of it.”5 There are multiple ways the Marines can make the Commandant’s vision a reality.
The Threat
The People’s Liberation Army Navy (PLAN) continues to mature its diesel-electric and nuclear-powered submarine fleets, with a goal of at least parity with the West—or even becoming the premier submarine force of the world. Analysts project that China’s submarine fleet will numerically exceed the U.S. fleet by 2030, while its quality will continue to improve.6 In their authoritative book, Red Star Over the Pacific, Toshi Yoshihara and James Holmes warn of the increasingly large and capable Chinese submarine force:
Over the past two decades, modern diesel submarines—difficult to detect, track, and target in shallow offshore waters—have slid down the ways at Chinese shipyards or been purchased in significant numbers from Russian suppliers.7
A 2015 RAND Corporation study indicated that the opportunity for submarine attack against a U.S. carrier strike group increased by an order of magnitude from 1996 to 2010 and projected the capability to increase by yet another order of magnitude by 2017.8 In 2018, Chinese President Xi Jinping personally addressed a new generation of submarine crews, saying:
Submarine forces are a key instrument of our nation and therefore must be given priority and make big strides in their development. . . . We pin our hopes on you to make rapid improvements in our Navy and its submarine forces.9
Western analysts also have noted that China continues to expand its shipyards, enabling the country to ramp up submarine production in the coming years.10
The submarine threat to the U.S. Navy’s sea control and power projection forces (aircraft carriers in particular) remains critical. Captain Wayne Hughes and Rear Admiral Robert P. Girrier’s book, Fleet Tactics and Naval Operations, reminds us that 15 aircraft carriers were sunk by submarines in World War II, a tally that nearly equaled the tonnage of carriers sunk by aircraft.11 Argentine forces possessed the potential to derail the entire British Falklands campaign with a single submarine. What effects would 76 Chinese submarines have in a great power conflict?12
Existing Capabilities
At the height of the Cold War, the U.S. Navy had 227 operational P-3 Orion ASW aircraft, organized in three dozen squadrons around the world.13 The P-3 fleet dwindled, as first the “peace dividend” at the end of the Cold War and then the war on terror made hunting submarines seem less relevant. The number declined to 137 by 2010. The last active-duty P-3 squadron retired its aircraft in 2019, and the follow-on P-8A is slowly ramping up. The Navy has set a requirement for 138 P-8As, but as of late 2019, only 111 were actually under contract.14 The Navy will supplement the P-8As with MQ-4C Triton unmanned aerial vehicles (UAVs), but these also will be spread very thinly.
Even though the P-8A is very capable, it will end up a high-demand, low-density asset. The United States fields 291 MH-60R Seahawk helicopters, and while these “Romeos” provide important shipboard ASW capability for prosecution and point defense, they lack the range, payload, and on-station time of the Boeing 737–derived P-8s. In any global conflict, P-8s would be spread thin protecting U.S. surface vessels. Even with 291 helicopters, it is not clear the Navy could meet the density of ASW assets (25 ASW helicopters) the Royal Navy deployed during the Falklands campaign without stripping protection from other regions.15
Also, the U.S. surface fleet is less capable in ASW than it should be, suffering from a similar distraction and warfighting atrophy as the Navy’s airborne ASW fleet. The Navy decommissioned the last of its frigates more than five years ago, and the littoral combat ships’ ASW mission modules have struggled to satisfy the problem-plagued platform’s restrictive weight requirements. Crucial systems are still in testing despite the first ship being commissioned more than a decade ago.16 The mission modules are expected to be operational soon, but Constellation-class frigates will not join the fleet until the mid-to-late 2020s, leaving the surface fleet with a significant ASW gap at the same time as the Chinese submarine fleet is expected to numerically surpass the U.S. submarine fleet. While guided-missile destroyers (DDGs) and guided-missile cruisers (CGs) have robust ASW capabilities—including hull-mounted and towed-array sonars and the capability of embarking Romeos—DDGs are, like the P-8s, high-demand, low-density assets with commitments outside the Indo-Pacific theater and missions beyond ASW. The vast expanses of the Indian and Pacific Oceans demand far more than the 10 to 14 DDGs and cruisers available in Seventh Fleet.17
Expeditionary ASW, Marine Corps Style
The joint force can address this ASW shortfall by using the Marines as extensions of the ASW bubble provided by DDGs and CGs. The Commandant of the Marine Corps has turned this former interservice heresy into something approaching doctrine.18
The Commandant’s message is clear: ASW should be considered a cross-domain mission supported by Marines. Marines can do so by supporting Navy forces at expeditionary advanced bases. P-8s and MH-60Rs could forward deploy, increasing their distribution and reach within the battlespace. Marine logistics could sustain these aviation units with the fuel, lightweight torpedoes, and sonobuoys needed for the ASW fight.19 Surface ships could launch intelligence, surveillance, and reconnaissance UAVs, including loitering munitions, under strict emissions control for subsequent control handoff to Marines (known as remote-split operations), thereby extending maritime domain awareness without compromising surface forces.
Beyond simply supporting the Navy’s ASW operations, Marines also can be actively involved in the detection and prosecution of enemy submarines with their own small boats and aircraft, or even from land.
Boats. Turning its focus toward the sea, the Marine Corps is considering acquiring a fleet of Metal Shark long-range unmanned surface vessels (LRUSVs).20 Despite the vessel’s small size, the LRUSV could be fitted with conventional miniaturized ASW sensors such as thin-lined, towed arrays (TLTAs) and hull-mounted sonars or deploy smaller unmanned systems. In fact, during 2016’s Operation Unmanned Warrior, four wave gliders successfully tracked a submarine using a Krait-Array TLTA.21 Also, LRUSVs could employ the small, lightweight torpedoes known as compact rapid attack weapons (CRAWs), making them an effective pounce platform for any Chinese submarines detected in their areas of operation. Capable of full autonomy, the vessels could be optionally manned with sailors and Marines to adjust the payload for the wide spectrum of ASW missions, including sensor deployment, target tracking, and target prosecution.
The LRUSV, however, is simply one option of many small craft available. The Coast Guard’s modern fast response cutters would also make a good manned platform for an ASW suite. The Marine Corps could also procure manned patrol boats that would be good candidates for ASW missions. Larger patrol boats would have advantages over LRUSVs in range and payload capacity.
MV-22s. The Marine Corps’ MV-22s are ideal candidates for enabling expeditionary ASW from EABs. Tilt-rotor aircraft could revolutionize ASW. The ability to land and take-off from austere locations provides a significant tactical advantage, because these aircraft do not need vulnerable fixed runways like the P-8 (which requires a mile or more of paved runway to take off). While Marines might sustain P-8s forward, the planes would be based primarily outside contested areas, which increases the P-8s’ transit time to operational areas. The MV-22’s faster speed, longer endurance, and midair refueling capability would make it better a ASW platform than the MH-60R Seahawk the Navy currently operates.
In October 2020, Medium Tiltrotor Squadron 163, a Marine Corps MV-22 squadron, deployed oceanographic sensors and buoys that demonstrated its usefulness in this role.22 Also, Bell Flight’s developmental tiltrotor aircraft, the unmanned V-247 Vigilant, touts antisubmarine warfare as a potential mission.23
Cross-Domain Fires. Ground-based fires are another way Marines could help fight submarines. The Marine Corps plans to increase its HiMARS missile artillery numbers by 300 percent and to develop a variant of the Joint Light Tactical Vehicle that can carry antiship missiles.24 Along the same lines, the Army has demonstrated and continues to develop capabilities for its rocket artillery. As a complement to these antisurface weapons, the Marine Corps could mate the CRAW with HiMARS-fired Guided Multiple Launch Rocket System (GMLRS) rounds to give its new littoral regiments a potent antisubmarine weapon. The Marine Corps could use these long-range rocket artillery batteries to prosecute detected submarines almost instantly.
Current GMLRS rounds with CRAW-sized warheads already have almost triple the range of the existing ship-launched RUM-139 antisubmarine rockets (75 km vs. 28 km), but the CRAW/GMLRS advantage will soon increase. The Army is investing to expand the GMLRS’s range to 150 km and field the new Precision Strike Missile (PrSM), with a range of more than 500 km.25 Mobile batteries with anti-ship and antisubmarine weapons would allow Marines to target any enemy vessel transiting critical chokepoints and littoral regions.
Resistance to Change
Despite the Commandant’s imprimatur, Marine Corps efforts to participate in ASW face resistance. After General Berger published the Commandant’s Planning Guidance outlining future changes to the Marine Corps, Jim Webb, a former Marine and Secretary of the Navy, forcefully argued that the Marine Corps should not optimize itself for the Pacific to support naval missions. He wrote:
After the centuries it took to establish the Marine Corps as a fully separate military service, it could reduce its present role by making it again subordinate to the funding and operational requirements of the Navy.26
Asking the Marine Corps to fight submarines at sea—historically a blue-water Navy mission—will certainly be met with skepticism by traditionalists from both the Navy and Marine Corps. But if the Marine Corps wants to stay relevant, it has to be willing to change and challenge the historical divisions of labor among the Sea Services. Even if the Marine Corps does pursue ASW, it will only be able to do so as a junior and supporting partner to the far better equipped Navy.
To the Shores of EABs
One of the most important lessons of the Falklands War is how seriously the U.S. Navy must take the submarine threat to its surface fleet. Although the Navy has recognized the importance of ASW, it will need help, and the Marine Corps should stand ready to assist by embracing ASW as a complementary mission.
The Marine Corps will not be directly involved with screening aircraft carriers or conducting deep-water ASW. But it could provide valuable capabilities in the littorals, and at key maritime chokepoints. The Marine Corps should develop multiuse capabilities that are compatible with the expeditionary advanced base operations concept for taking the fight to enemy submarines. General Jeremy Moore, commander of the British ground forces during the Falklands War, said of the conflict, “Only land forces could win the war, but the Navy could always lose it.”27
1. Sebastien Roblin, “How the Falklands War (Thanks to a Stealthy Submarine) Could Have Gone Very Differently,” The National Interest, 27 November 2016.
2. Chris Hobson and Andrew Noble, Falklands Air War (Hinckley, UK: Midland Publishing, 2002), 157–58; John Lehmann, “Reflections on the Special Relationship,” Naval History 26, no. 5 (September 2012).
3. Norman Friedman, “The Falklands War in Retrospect: Hard Lessons from a Small War,” Defense Media Network, 2 April 2015.
4. Craig Lokkins, “The Falklands War: A Review of the Sea-Based Airpower, Submarine and Anti-submarine Warfare Operations,” (thesis, Maxwell AFB, AL: Air War College, 1990).
5. GEN David H. Berger, USMC, “Marines Will Help Fight Submarines,” U.S. Naval Institute Proceedings, 146, no. 11 (November 2020): 18–23.
6. H. I. Sutton, “U.S. Navy Submarine Fleet to Be Overtaken by China Before 2030,” Naval News (13 December 2020).
7. Toshi Yoshihara and James R. Holmes, Red Star Over the Pacific: China’s Rise and the Challenge to U.S. Maritime Strategy, 2nd ed. (Annapolis, MD: Naval Institute Press, 2018), 182.
8. “Chinese Threat to U.S. Surface Ships,” 2017 research brief, The RAND Corp.
9. “Chinese President Xi urges Navy to Boost Combat Readiness, Build Aviation Force,” The Straits Times, 16 June 2018.
10. H. I. Sutton, “Chinese Increasing Nuclear Submarine Shipyard Capacity,” USNI News, 12 October 2020.
11. CAPT Wayne P. Hughes Jr. and RADM Robert P. Girrier, USN (Ret.), Fleet Tactics and Naval Operations, 3rd ed. (Annapolis, MD: Naval Institute Press, 2018), 117.
12. David Axe, “China’s Navy Could Have 76 Submarines by 2030: Report,” The National Interest, 30 April 2020.
13. Loren Thompson, “U.S. Navy Plans to Stop Buying P-8 Poseidon Sub Hunter Despite Growing Undersea Threat,” Forbes, 2 December 2019.
14. Office of the Secretary of Defense, “Selected Acquisition Report: P-8A Multi-Mission Maritime Aircraft,” December 2018.
15. “MH-60R Seahawk Multi-Mission Naval Helicopter,” Naval Technology.
16. Ronald O’Rourke, “Navy Littoral Combat Ship (LCS) Program: Background and Issues for Congress,” Congressional Research Service (17 December 2019).
17. “The United States Seventh Fleet” Seventh Fleet, 12 September 2019; Richard Burgess “Navy Plans to Retire 48 Ships During 2022–2026,” Sea Power, 11 December 2020.
18. Berger, “Marines Will Help Fight Submarines.”
19. Walker D. Mills, Dylan Philips-Levine, and Collin Fox, “Cocaine Logistics for the Marine Corps,” War on the Rocks, 22 July 2020.
20. Jared Keller, “The Marine Corps Is Eyeing a Long-range Robot Boat That Can Nail Targets with Kamikaze Drones,” Task & Purpose, 27 January 2021.
21. C. Tucker, “UDT 2019—Anti-submarine Warfare (ASW) Towed Array,” Undersea Defense Technology, 1 July 2020.
22. “Making History with VMM-163: Squadron Deploys Oceanographic Sensors,” U.S. Marine Corps website, 22 October 2020.
23. “Unmanned & Unmatched.”
24. Philip Athey, “New in 2021: Why the Corps Might See Fewer M777s Next Year,” Marine Corps Times, 30 December 2020.
25. Jen Judson, “Army, Lockheed Prep for First Extended-Range Guided Rocket Test Firing,” Defense News, 13 October 2020; Kyle Rempfer and Joe Gould, “U.S. Army Completes Third Test of Lockheed’s Precision Strike Missile,” Defense News, 30 April 2020.
26. Jim Webb, “The Future of the U.S. Marine Corps,” National Defense Magazine, 8 May 2020.
27. Steven Harper, Submarine Operations during the Falklands War (thesis, Newport, RI: Naval War College, 1994).