As the United States refreshes the nuclear triad, gearing up to build 12 big Columbia class (SSBN 826) ballistic missile submarines, the U.S. Marine Corps is exploring the feasibility of dispersed operations, de-emphasizing legacy “land on the beach” amphibious assault concepts for smaller, more agile “raider-like” teams.
For the forward-looking Marines, troop-carrying variants of the Columbia class, tacked on at the end of the ballistic missile submarine production run, might be a good investment. But the Marine Corps may not have the chance.
Congress is brow-beating the Navy for backing away from a “handshake agreement” on a $9 billion multiyear contract for three pricey LPD-class amphibious transports and one LHA-class mini-carrier, a step that locks the the Navy into an old-school, Cold War-era amphibious force structure.
Amphibious assault ships are useful, but this effort to preserve industrial capacity ignores the Pentagon’s concerns that amphibious assault has fundamentally changed. Landings are becoming a far more stealthy endeavor, requiring a wider range of assets than the Navy’s traditional set of big and expensive amphibious assault ships.
One of those new assets for the new battlefield might well be a big submarine dedicated to amphibious assault, supplemented by a range of cheaper Lewis B. Puller Class Expeditionary Support Bases or other converted platforms. Over the next few years, as the Marine Corps figures out how small teams of 75 to 100 Marines will fight from a new fleet of 20-30 “presence-minded” Light Amphibious Warship (LAW) “concept” vessels, the Pentagon is going to start mulling how undersea platforms can help their smaller, LAW-sized Marine contingents make a difference in more highly contested areas—areas that can only be approached from undersea.
It can be done. But one big problem is that the only U.S. submarines currently able to easily embark, insert and recover a contingent of about 70-100 Marine raiders are aging out. The four Ohio class guided missile submarines, the former ballistic missile submarines USS Ohio (SSGN 726), USS Michigan (SSGN 727), USS Florida (SSGN 728) and USS Georgia (SSGN 729), will start retiring by around 2028.
It is time to consider adopting the Columbia class missile boat design for other missions. The Navy has found that the big, flexible missile subs, once converted and freed of the nuclear deterrence mission, are both popular and useful. Aside from troops, the enormous subs carry a lot of offensive weaponry that the Navy is already racing to replace. To make up for the estimated 154 Tomahawk cruise missiles the four converted Ohio class cruise missile submarines can deploy, the Navy is turning to the legacy Virginia (SSN 774) class attack submarine. Over the coming years, the Navy plans to purchase at least 12 “stretched” Block V Virginia class attack submarines for missile-carrying duties. Lengthened and equipped with big, multi-mission Virginia Payload Module containers, the Navy is eager to use the new subs to reconstitute the lost Ohio class missile tubes, using them to test out the conventional Prompt Global Strike ballistic missile concept.
On the other hand, the fate of the Ohios’ legacy commando support mission is not being openly discussed. Certainly, older Virginia class submarines can, by sacrificing a fully functional torpedo room, take up the slack by berthing a Marine platoon or some 40 special operators. But even though commando gear can now be packed into Virginia Payload Modules, space will still a problem—even aboard the bigger Block V Virginia class subs. The smaller attack submarines will certainly be hard-pressed to embark 70 to 100 Marines, and it will be nearly impossible to accommodate all the various armories, munition storage areas, staging rooms, berthing and mission planning areas Marine raiders need to be fully effective without compromising the attack submarine’s ability to fight other ships and subs.
Procuring a few Columbia class submarines to support a commando/unmanned craft mothership-type mission might be quite useful. In fact, it may well be time to start planning a commando-oriented Colombia class variant to be added into the production line just as Columbia class ballistic missile submarine production winds down. If the Pentagon is serious about reorienting the Marine Corps towards distributed operations and shifting from the fleet structure detailed in the Navy’s longstanding 355-ship goal, it is quite possible the Marine Corps could continue to radically shift amphibious vessel requirements, shedding some $20 billion to $30 billion in conventional large, multi-billion-dollar amphibious assault vessel recapitalization costs over the next 30 years. With that kind of divestment, the Marines could well afford a few Columbia class “battle taxis,” growing the existing program-of-record from 12 submarines to 14, or even more.
Distributed Operations: The Return of Carlson’s Raiders
Undersea deployment of Marines is not a stretch. The United States Marine Corps have done this for years and the organization has a long history of employing big submarines for various types of amphibious assault. As far back as World War II, the extra-large USS Argonaut (SS 166), USS Narwhal (SS 167) and USS Nautilus (SS 168) were drafted to support a range of amphibious raids, scouting teams and clandestine operators.
At almost twice the displacement of the Navy’s numerous Gato, Balao and Tench class attack submarines, the Navy’s three balky, ersatz troop transports demonstrated their value, landing over 200 Marine Raiders to assault Makin Atoll in 1942, helping recover the Alaskan island of Attu in 1943, and supporting resistance and landing forces throughout the Pacific basin. As, basically, single-mission ships, they were not great ship-sinkers, and the unwieldy USS Argonaut was lost after trying to attack a convoy.
While the Navy’s more numerous smaller submarines were also employed in amphibious support roles, the potential utility of larger submarines in amphibious assault was reinforced after the war. In 1945, the Submarine Operations Research Group, charged to evaluate America’s wartime experiences in identifying potential new missions for future submarines, suggested the Navy support a requirement for undersea amphibious assault-oriented troop carriers.
That initial requirement, grown out of World War II experiences, has remained relatively unchanged for more than 75 years. The ability to deploy a good number of commandos from undersea platforms is an enormously useful capability, and the Navy has, ever since the mid-’60s, always managed to set aside a few large submarines for amphibious endeavors.
Undersea Troop Carriers Have A Long Record Of Success:
While the requirement for undersea commando transport has endured, troop transport—undersea or otherwise—has never really has been a major Navy priority. But the undersea troop carrier mission has been a fleet constant since World War II, and the operational concepts backing the viability of amphibious assault submarines have been tested, retested and tested again, even as the Navy shunted commando transport to cast-offs and near-obsolete boats.
In 1948, several tired World War II-era attack submarines were converted into transport subs. With the capability of carrying up to 160 Marines, two stripped-down Balao class submarines, USS Perch (SS 313) and USS Sealion (SS 315), were given the unwieldy classification of “Amphibious Vessels, Submarine Transport,” carrying out a range of ground-breaking operational tests with armored amphibious vehicles, helicopters and troops. After 25 years of service and supporting amphibious operations during the Korean and Vietnam wars, they were both retired in 1969.
The demise of the Regulus submarine-launched cruise missile program in 1964 offered another opportunity for the Navy to pursue troop-carrying conversions. The advanced communications aboard the Regulus-armed submarines, coupled with their commodious missile storage hangars, let newly converted Regulus-launching subs enjoy a second career supporting special operators. The Regulus-firing USS Tunny (SS 282), a World War II-era Gato class attack submarine, was the first troop carrier conversion, followed by the repurposing of the brand-new missile-carrier USS Greyback (SSG 574). Both subs served in Vietnam, enjoying full, 25-year careers. Ironically enough, in 1986, the USS Greyback, in a grim presage of today’s maritime challenges, was sunk as a target in the South China Sea.
In 1981, strategic arms limitation efforts let commandos experience America’s commodious strategic missile submarines for the first time. Initially, two obsolete Ethan Allen class ballistic missile submarines, USS Sam Houston (SSN 609) and USS John Marshall (SSN 611), swapped their tired Polaris ballistic missiles for a contingent of about seventy commandos. A few years later, as Poseidon ballistic missile-firing subs were yielding to the new Trident missile family, two Benjamin Franklin class missile subs, the USS James K. Polk (SSN-645) and USS Kamehameha (SSN-642), exchanged their missile tubes for the capability to transport and deploy about seventy commandos as well.
The end of the Cold War released four of America’s 18 relatively new 18,700-ton Trident II-firing Ohio class ballistic missile submarines for new duties. By 2008, four Ohio conversions had re-entered service, marrying troop-carrying capacity with space for up to 154 cruise missiles or other gear. Like the Ethan Allen and Benjamin Franklin class conversions, the Ohio class guided missile conversions can berth and deploy teams of around 70 to 100 troops. As an in-demand asset, popular with their crews, the flexible Ohio class conversions have been a smashing success.
Time To Design SSBN Variants For Undersea Amphibious Assault
For the past 50 years, the transition from one class of undersea strategic deterrent platform to another happened rather quickly, always offering a few relatively spry, middle-aged missile subs a chance to enjoy a second life as a glamorous commando-carrying platform. That will not happen with the transition away from the Ohio class to the Columbia Class missile boats.
The old Ohio class subs simply won’t have enough life left to convert. Already anticipating production delays, the Navy is looking to eke a few more “final” patrols out of the aging Ohios. And while the Virginia class submarines can fill in by supporting commandos, the Navy, with the Block V Virginias, is focusing more upon replacing the Ohio’s lost cruise missile throw-weight and is less interested in having their new attack subs doing the dangerous and dirty duty of schlepping future Marine Corps units into combat. But if the Marine Corps sees potential in operating from big undersea amphibious assault platforms, the Department of Defense needs to start setting the stage now, preparing Congress, the taxpayers and the industrial base to better understand the Marines’ sneaky, low-profile future. Either that, or Congress and Industry, for lack of anything better to do, will keep forcing the Navy to buy a bunch of old-school platforms that, while optimized for the Cold War, won’t work very well in the conflicts to come.