No naval professional can read the under secretary’s article and the CNO’s guidance without hearing the general alarm: It’s time to move out smartly. These documents constitute a clear call for action that finds the balancing point between our new resources and our new goals. For undersea warriors, the President’s Sustaining U.S. Global Leadership and the CNO’s two documents are sobering, amplifying our historic role of controlling the global commons on the seas while facilitating naval and joint-force access. A few excerpts illustrate the pivotal role that undersea forces must play in the future security environment (italics added):
Sustaining U.S. Global Leadership: The Blueprint
• The U.S. military will invest as required to ensure its ability to operate effectively in anti-access and area-denial (A2/AD) environments. This will include implementing the Joint Operational Access Concept, sustaining our undersea capabilities , developing a new stealth bomber, improving missile defenses, and continuing efforts to enhance the resiliency and effectiveness of critical space-based capabilities.
• Maintain a Safe, Secure, and Effective Nuclear Deterrent . As long as nuclear weapons remain in existence, the United States will maintain a safe, secure, and effective arsenal.
Guidance from the CNO
From Sailing Directions :
• The Navy will continue to dominate the undersea domain using a network of sensors and platforms—with expanded reach and persistence from unmanned autonomous systems.
And from Navigation Plan :
• Increase near-term mine warfare capability with . . . unmanned underwater vehicles (UUVs) for shallow and bottom-mine detection.
• Build proven ships and aircraft: Arleigh Burke –class destroyers, San Antonio –class amphibious ships, Virginia -class submarines, MH-60 R/S hel-icopters, F/A-18 Super Hornets, E/A-18 Growlers, and E-2D Hawkeyes.
• Improve the reach of today’s platforms through new payloads of more capable weapons, sensors, and unmanned vehicles to include . . . submarine-launched conventional strike weapon.
• Continue to dominate the undersea environment with a combination of Virginia -class submarines, Virginia -class payload modules, improved torpedoes such as the Mk 54 lightweight torpedo and P-8A high-altitude ASW weapon capability, and large displacement UUV.
• Maintain credible and survivable strategic deterrence; develop SSBN(X) as the Ohio -class replacement while maintaining today’s number of available SSBNs.
• Improve ASW sensor reliability and performance, including towed-array maintenance and modernization.
• Increase the inventory of decoys, sonobuoys, and torpedoes for Fleet ASW training.
• Sustain Fleet Synthetic Training to provide a wider range of complex and demanding simulations than possible in the field, while conserving operating expenses where appropriate.
The Navy’s submarine force leaders have been focused on the responsibilities posed by the new security environment. On 20 July 2011, the anniversary of the first launch of a Polaris missile from the USS George Washington (SSBN-598) in 1960, the Design for Undersea Warfare was promulgated to address today’s challenges. It was structured along three lines of effort: Operations and War-fighting, Ready Forces, and Future Forces.
This went far to align our capabilities in support of achieving tangible goals, and to guide the undersea force’s activities to maintain superiority in that domain. As we begin the process of updating the design in light of the new strategic guidance, we can use lessons of the past to navigate the waters of the future. And as we undertake this responsibility to execute our higher commander’s guidance, it becomes apparent that we are at the dawn of a fourth generation of undersea warfare.
Generation I: The Basics
The first undersea-warfare generation focused on designing a submarine that could succeed as a viable warship. The rapid change in submarine technology during this era is reflected in the career of Fleet Admiral Chester Nimitz, who commanded the USS Plunger (SS-2) as an ensign in 1909. The Plunger was a small seven-man submarine that could go only 8.5 knots on the surface, stay submerged for 4 hours at slow speed, and carry 2 torpedoes. Thirty-two years later, as a four-star admiral, Nimitz assumed command of the Pacific Fleet on board the 70-man submarine Grayling (SS-209), which could go 21 knots on the surface, stay submerged for 48 hours at 2 knots, and carry 24 torpedoes. 2
Throughout much of the first generation, submarine operations, tactics, training, characteristics, design, and construction were dictated by the requirements of War Plan Orange, the U.S. Navy’s strategy for its most likely adversary, Japan. It charged the submarine force with supporting the U.S. Fleet as it sailed into the western Pacific Ocean to conduct an island-hopping campaign that would ultimately lead to the blockade of Japan. 3 To support the plan, the submarine force identified two primary missions: operating independently in enemy waters in place of aircraft and surface ships, and as a scout ahead of the fleet, or as a naval skirmisher to soften up the enemy fleet before the surface fleet engaged. 4 To accomplish these missions, the ideal “fleet submarine” required long range, high surface speed, and sufficient weaponry. 5
Unfortunately, based on an unrealistically conservative assessment of adversary antisubmarine capabilities, the submarine force prepared for combat with canned training exercises in which potential targets zigzagged while under heavy protection by extremely alert aircraft and surface vessels. To avoid detection (and criticism from their superiors) in these challenging scenarios, submarine commanders developed tactics to operate slowly, remain below 125 feet, and rely on passive sonar for an attack. 6
Within five hours of the attack on Pearl Harbor, the strategic rationale that underpinned the fleet submarine’s design and doctrine was jettisoned when CNO Admiral Harold R. Stark ordered unrestricted submarine warfare against Japan. No longer able to scout ahead of the sunken battle fleet, the submarine force instead sailed out to commence warfare and conduct operations independent of the Fleet. Entering the war largely unprepared for the mission that faced them, while remaining innovative and persistent, these submariners defined the second generation of undersea warfare. 7
Generation II: Warfighting Sea Legs
Nimitz said of the World War II Pacific Fleet: “It was to the submarine force that I looked to carry the load until our great industrial activity could produce the weapons we so sorely needed to carry the war to the enemy.” The story of the successful U.S. submarine campaign against Japan has been chronicled many times and need not be discussed in detail. Although fleet submarines were not designed for commerce raiding, their characteristics made them perfect commerce raiders in a warfighting domain defined by the broad geography of the western and South Pacific. It’s also important to note that although the primary mission of the World War II submarine force was commerce interdiction, subs proved exceptionally versatile, sinking a lion’s share of the Japanese navy, landing commandos in the South Pacific, conducting photo reconnaissance of beaches for amphibious landings, and acting as lifeguards for downed naval aviators. 8
This warfighting environment required a shift in tactics and training, accompanied by a similar change in commanding officers. Within three years the age of the youngest U.S. submarine commanders dropped by a decade, and younger officers boldly charged into situations that leaders would never have countenanced before the war. As a result, and after overcoming significant difficulties with inappropriate tactics and malfunctioning torpedoes, U.S. submarines sank 55 percent of all Japanese ships. 9
A great deal of the success in Generation II was due to the technical excellence of the U.S. submarine force’s industrial base—a quality that continues today. During Generation I, there were many shipbuilders and different “classes” of submarine, as the daring inventors and operators drove to develop a vessel that could be used as a warship. The motivation that guided the development of the fleet boat was to prove obsolete after the attack on Pearl Harbor, as noted previously, but the innate benefits of speed, endurance, stealth, and payload proved supremely useful when the mission switched to commerce raiding.
While doctrine, leadership, and torpedo development all needed major revisions to become effective, the basic fleet boat, first the Tambor and then the Gato and Balao classes, was largely the same basic design; no major revolutionary changes occurred from one class to the next. What did happen was a steady evolutionary pace of advancement, both between successive classes but also, importantly, within a given class.
Comparison of any fleet boat at the war’s beginning with one in 1945 makes clear the warfighting impact of evolutionary upgrades in weapons (guns and eventually torpedoes), radios, and sensors—particularly the SJ Radar, which enabled the “end around” tactic against enemy shipping, in which a sub could determine the course and speed of a target from ranges over the horizon and out of visible range, while remaining undetected on the surface. There, faster speed enabled the crew to take a position ahead of the target, submerge on its track, and wait for it to come toward the attack. Innovative advances such as these made new tactics possible and served to keep the enemy off balance throughout the war. The evolutionary approach to advancement continues today: Los Angeles –class submarines for years have benefited from the Advanced Rapid COTS Insertion (ARCI) model that leverages commercial technologies to keep sensors, processors, and software paced with industry’s advances. This has resulted in significant warfighting-capability gains and equally important cost avoidance. The approach of evolutionary innovation and improvement within a submarine class has become fully integrated into the design of today’s Generation IV Virginia -class submarine.
But the most important development of this period was that “the submariner” became truly defined. This unique sailor was a dedicated team player in a high-stakes part of the war. The submarine force was always all-volunteer. These service members were first subjected to intense training in Submarine School, where engineering, tactics, and survival skills were taught. Only the very best passed the test and reported to the fleet, where another challenge—submarine qualification—began.
New sailors had to learn every aspect of the boat, essentially being able to perform any job on the vessel at sea. The combination of the rigorous qualification standard, confined quarters below the sea, highly classified operations, and extreme danger formed the “Silent Service,” a tightly bound band of undersea warriors that comprised only about 6 percent of the Navy’s people. That share is largely intact today.
These submariners were masters of innovation and creativity. Armed with deep expertise and innate intelligence and stamina that allowed for precise teamwork, they were able to outthink, outlast, and outfox the enemy. It was they, more than any other weapon in the arsenal, who were key to the submarine force’s success. This remains true today.
At the end of World War II, the U.S. submarine force briefly found itself in a period of transition and drastic reductions. But the force went forward with the development of greater underwater propulsion power submarines, which incorporated streamlined hulls, advanced batteries, and snorkels, making possible extended submerged underways and higher underwater speeds. It was also during the late 1940s and early 1950s that the submarine force began the research and development of nuclear-powered and teardrop-shaped submarines, bringing about the third generation of undersea warfare. 10
Generation III: Nuclear and ASW Strategic Deterrence
In 1992, when the strategic submarine force completed its 3,000th strategic-deterrent patrol (by the USS Tennessee [SSBN-734]), General Colin Powell noted that “America’s nuclear-powered ballistic-missile submarine fleet” had been largely responsible for winning the Cold War. The submarine force’s wisdom in persevering with development was validated as the Soviet navy’s submarines became increasingly advanced and the United States fully committed to the newly established NATO. In the event of a third world war, the fate of the free nations of Europe would depend on the rapid resupply of the outnumbered NATO forces. Just as did the Germans with U-boats in World Wars I and II, the Soviets would undoubtedly attempt to interdict these convoys in the Atlantic. This threat alone justified a significant investment in antisubmarine warfare. 11 The strategic reality of the Soviet presence in Europe dictated a new mission for the U.S. submarine force.
Additionally, in the late 1950s, following the development of the intercontinental ballistic missile, both the U.S. and Soviet navies feverishly worked to develop the submarine-launched ballistic missile (SLBM). With the ability to relocate almost anywhere in world and remain hidden from aerial reconnaissance, SLBMs proved to be the most survivable and reliable leg of the nuclear triad. For the U.S. submarine force, the rise of SLBMs reinforced the importance of antisubmarine warfare as well as creating a new mission: strategic deterrence. 12 As intelligence would eventually make clear, the primary mission of the Soviet submarine force was to establish secure bastions near the homeland in which their strategic submarines could remain under way and hidden. By this means they hoped to preserve a decisive and survivable strike capability. Once this Soviet strategy was discerned, it became a primary mission of the U.S. submarine force to hold those Soviet SSBNs at risk.
Both antisubmarine warfare and strategic deterrence required submarines with an acoustic advantage and the ability to remain submerged for prolonged periods. After significant experimentation and innovation, the Silent Service achieved the acoustic advantage through better sonars, superior sound silencing, and an understanding of oceanography. Simultaneously, the submarine force harnessed the advantage of nuclear power. This meant the vessels could remain submerged indefinitely and travel immense distances at high speed, with no need to refuel or spend significant time at periscope depth for air. 13
By the end of the Cold War, the submarine force had successfully performed as a credible and reliable U.S. nuclear deterrent, holding at risk the Soviet ballistic-missile submarine force. This achievement, in the absence of any combat evolutions that would have validated or invalidated the force’s strategy, was almost unprecedented. It required “the kind of technical and doctrinal innovation which is normally considered rare in military organizations in peacetime.” 14
Much as occurred during the gradual transition between the second and third generations near the end of World War II, no sharp divide separated the third and fourth generations near the Cold War’s end. Although the Soviet menace vanished almost overnight, highly capable adversaries did not disappear. The submarine force has had to continue to execute missions similar to those of the Cold War. Precision strike had already emerged, but it evolved and became the submarine force’s primary combat mission area of the 1990s. 15
Despite the lack of a monolithic adversary threat, the force knew it needed to evolve its capabilities to keep pace with those of potential threats. Much as its leadership at the end of World War II embraced the potential of nuclear power and correctly chose to explore new designs and technologies, the submarine force at the end of the Cold War appropriately embraced the promise of advanced computer processing and digital technology, producing a superior and effective replacement for the Los Angeles class with the Virginia . And just as the undersea challenge of the Cold War did not become fully clear until the USS Nautilus (SSN-571) was in the water, the situation confronting Generation IV is just now becoming clear. A new security environment is taking shape, and Virginia -class submarines are joining the Fleet in growing numbers.
Generation IV: Undersea Networks
The maritime-security environment that distinguishes Generation IV is largely defined by two broad trends. One is the movement toward increasingly pervasive combat networks that combine ubiquitous intelligence, surveillance, and reconnaissance; longer-range, responsive, and precise weapons (including cyber and space weapons with near-instantaneous global reach); and increasingly high-bandwidth command-and-control networks to connect the ubiquitous sensors with the longer-range weapons. The other trend is the persistence of very simple weapons—groups of mines, salvos of rockets, swarms of small craft—that can impose an asymmetric cost even on an advanced force in a close-quarters fight.
The combination of these rapidly proliferating approaches permits adversaries to attack from close in or at great distance—concentrated in time and space with unprecedented precision. Consequently, our Navy’s traditional standoff ranges have become less and less protective. More than ever, it is easy to be “seen,” which can lead to being targeted and, increasingly, hit. These trends combine in ways that are tailored to the user, to produce a uniquely designed system of systems that can deny access to an area altogether, or can severely limit freedom of action within an area—an A2/AD network.
The implications for undersea warfare are far-reaching. Just as in World War II, our missions in the A2/AD environment will pertain to operating in increasingly large areas of the maritime domain where non-stealthy forces are more vulnerable to attack. While many forces will be working to fight from the “outside in,” undersea forces will fight from the “inside out,” working closely with other low-profile forces (such as stealth aircraft and special-operations forces) within the A2/AD radius, to create chaos and disruption for the enemy and opportunities for our joint force. These operations will be focused on using the stealth, endurance, and payload of undersea forces to exercise freedom of maneuver inside an aggressor’s network barriers and enable access for the rest of the Navy and joint force. In other words, networked undersea forces will act as a key to unlock the door for decisive force to enter the fight and seize and maintain the initiative.
Not a Moment to Lose
As the saying goes, “If you want a new idea, read an old book.” As we work to expand the concept from submarine force to undersea forces—networked manned and unmanned platforms and sensors—to achieve decisive effect in Generation IV, it is instructive to remember successes from past generations. We must do this with some urgency.
As a top priority, we need to replace the sea-based leg of the strategic-deterrent force. This imperative will remain as far into the future as we can see. Both Sustaining U.S. Global Leadership and the Navigation Plan call out this requirement. We need to get the design right, fully considerate of affordability, and we need to execute within cost and schedule. But we must also be mindful that we cannot afford to build the undersea version of the B-18 bomber. This aircraft—designed, purchased, and built during the Depression in the 1930s—proved almost useless on delivery. It was deficient in range, speed, bomb load, and defensive capability. The submarine class that replaces the current Ohio -class SSBNs potentially will be in service until the 2080s, and we must get it right the first time for the critical and challenging mission it will execute.
Other areas in which the undersea forces should look for lessons from the past include communications security and payloads. The need for the former is hardly a new concept to the submarine force. Indeed, the lack of communications security doomed German efforts to win the Battle of the Atlantic in World War II. Despite a popular narrative to the contrary, Grand Admiral Karl Dönitz’s Wolfpack strategy required significant ship-to-shore transmissions, which allowed Allied escorts to localize U-boat positions with high-frequency direction finding and also to outflank the boats’ positions once the Enigma codes had been broken. 16
But it is an oversimplification to merely turn off radios and operate in EMCON. The need for communications security is in direct tension with a network, which it will take to defeat the A2/AD networks we confront. Prioritized, secure communications techniques are an imperative. So too is developing a cadre of leaders, from the strategic to tactical level, who can craft and employ effective mission-type orders that do not rely on continuous high-bandwidth comms, but succeed by promulgating thoughtful commander’s guidance that allows subordinate commanders to take advantage of local opportunities, advance the campaign, and provide feedback.
Strike warfare is an excellent example of this tension. Currently, strike from a submarine requires extensive radio communications, with multiple masts exposed out of the water. Although this was not a significant vulnerability against low-end enemies, it will be fatal against high-end adversaries whose drones are continuously searching to sight periscopes or masts and whose shore-side or space-based antennae are scanning all radio frequencies and locating the transmitters. Consequently, before we consider conducting strike warfare or cyber warfare inside an advanced A2/AD network, we must simplify and minimize communications, provide more independence to commanders, and research and develop new technologies that will permit less-vulnerable communications with our undersea forces, even when they are deep.
Winning inside an A2/AD network will also require us to update our weapons and payload inventory. Right now our submarines carry a mixture of Mk 48 Advanced Capability (ADCAP) torpedoes and Tomahawk land-attack missiles (TLAMs). Although ADCAP was originally designed to destroy high-speed, deep-diving Soviet Alfa -class titanium-hulled submarines, a program of ongoing evolutionary enhancements has enabled it to remain effective against a broad range of ship and submarine threats. 17 However, it is still a single heavyweight acoustic homing torpedo, and limitations in range and ability to treat diversifying undersea targets must be addressed.
Similarly, although the TLAM has been an evolutionary workhorse in precision strike, it may not have the range or hold the punch necessary to disable targets in a modern, fortressed battle network. As we update our various categories of undersea payloads to address the broader array of targets we need to hold at risk, and as we anticipate the implications of a smaller undersea force, we need to plan for the necessary changes in the undersea payload volume on our newest attack submarines.
Meet the New Realities
Finally, we need to renew our studies about how to optimally employ limited undersea assets. Admittedly, it would be great if we had the luxury to pick and choose missions that we will no longer execute. But the enemy gets a vote. Today’s strategic environment is like a game of three- or four-player chess—in a battlespace consisting of geographic, oceanographic/acoustic, and, increasingly, cyber/information layers. In our current fiscally tight environment, we must look to increase the flexibility and capacity of the submerged payload, then prioritize limited available undersea assets and deploy them where they are most needed. This requires full teaming of submarines with land, surface, and air forces to launch, employ, and recover undersea payloads when it is optimum for them to do so. Undersea forces must expand and enhance the impact of the current submarine force.
Once again, this experience is not new. Our predecessors—even in the first generation, during the fiscally lean decades of the 1920s and 1930s—held numerous conferences and studiously analyzed the results of war games at the Naval War College and Fleet Problems at sea to assess the best characteristics, tactics, and new technologies required to create the fleet submarine. 18 The periods after World War II and the Cold War were marked by extremely creative approaches to employing new technologies.
Working with the Naval Warfare Development Command and Naval Undersea Warfare Command, today’s undersea forces are conducting war games and seminars to identify concepts and technologies that should be researched and possibly developed. Among some of the exciting capabilities with which we are forging ahead are UUVs (including armed), cyber-warfare, and soft-kill technologies. We are working to ensure that we do not repeat the painful experience of Generation II, when we were a force unprepared for the conflict that arrived on our doorstep. In future warfare, it is unlikely we will have the time to “regroup” that we had at the beginning of World War II.
The President, Secretary of Defense, and CNO have given us clear direction and a call to action. As the character of Generation IV of undersea warfare becomes clear, the concepts, technologies, and, most important, dedicated and adaptive people must deliver against the challenges of the new security environment. Just as our past generations of undersea warriors were courageous in adversity and relentless in their pursuit of new opportunities, we fourth-generation undersea warriors must be bold and visionary. It’s time to get under way, rig for dive, and submerge ourselves in meeting the new realities of this era.
2. J. L. Christley, United States Naval Submarine Force Information Book (Marblehead: Graphic Enterprises of Marblehead, MA: 2000), 19, 41–42. E. B. Potter, Nimitz (Annapolis, MD: Naval Institute Press, 1976), 19, 62.
3. Michael Vlahos, The Blue Sword: The Naval War College and the American Mission, 1919–1941 , U.S. Naval War College Historical Monograph Series, no. 4 (Newport, RI: Naval War College Press, 1980), 118. Edward S. Miller, War Plan Orange: The U.S. Strategy to Defeat Japan, 1897-1945 (Annapolis, MD: Naval Institute Press, 1991), 28–38, 363–69.
4. RADM C. S. Freeman, Commander Submarine Force to the CNO, Subject: Submarines – Employment of in a Pacific War, 27 July, 1938; 420-15 1938; Box 112; Subject File 420-15; General Board, Subject File 1900-1947; General Records of the Department of the Navy, Record Group 80; National Archives Building, Washington, DC, 1.
5. Gary E. Weir, Building American Submarines, 1914–1940 , Contributions to Naval History, no. 3 (Washington, DC: Naval Historical Center, 1991), 40–43.
6. W. J. Holmes, Undersea Victory: The Influence of Submarine Operations on the War in the Pacific (Garden City, NY: Doubleday, 1966), 47–48. Randy Papadopoulos, “Between Fleet Scouts and Commerce Raiders: Submarine Warfare Theories and Doctrines in the German and U.S. Navies, 1935–1945,” Undersea Warfare 7, no. 4 (summer 2005): 31–32.
7. Joel Ira Holwitt, “Execute Against Japan”: The U.S. Decision to Conduct Unrestricted Submarine Warfare (College Station: Texas A&M University Press, 2009).
8. Clay Blair Jr., Silent Victory: The U.S. Submarine War Against Japan (Philadelphia, J. B. Lippincott, 1975).
9. Ibid., 107, 818, 877–79. Keith Wheeler, War Under the Pacific (Alexandria, VA: Time-Life, 1980), 21–23.
10. CAPT Raymond D. Woolrich, “The Years of Innovation,” in David Randall Hinkle et al., eds., United States Submarines (Annandale, VA: Naval Submarine League), 201–2. Henceforth: United States Submarines .
11. Owen R. Cote, The Third Battle: Innovation in the U.S. Navy’s Silent Cold War Struggle with Soviet Submarines , Naval War College Newport Papers no. 16 (Newport, RI: Naval War College Press,) 15. CAPT James C. Hay, “Cold War Submarine Confrontation,” in United States Submarines , 201–2.
12. Cote, The Third Battle , 20, 26, 51, 63–64. VADM Joe Williams, “A Cold War Retrospective,” in United States Submarines , 185–87. Hay, “Cold War Submarine Confrontation,” in United States Submarines , 203. CAPT Richard T. Wright, “Submarines in Strategic Deterrence,” United States Submarines , 209–12.
13. Williams, “A Cold War Retrospective,” in United States Submarines , 181–92. Cote, The Third Battle , 21–30, 41–50.
14. Cote, The Third Battle , 40.
15. Williams, “A Cold War Retrospective,” in United States Submarines , 190–92.
16. Blair, Silent Victory , 372–378. Blair, Hitler’s U-Boat War: The Hunters, 1939–1942 (New York: Random House, 1996), 476–77. Blair, Hitler’s U-Boat War: The Hunted, 1942–1945 (New York: Random House, 1998), x–xii, 791–92.
17. Cote, The Third Battle , 59.
18. RADM Thomas C. Hart, Commander Control Force, to the CNO, Subject: Results of Study of Submarine Warfare in Conference at Submarine Base, New London, and Recommendations on Submarine Design, 31 March 1931; 420–15, 1931–1933; Box 111; Subject File 420-15; General Board, Subject File 1900-1947; General Records of the Department of the Navy, Record Group 80; National Archives Building, Washington, DC.
Lieutenant Holwitt serves as the navigator on board the USS New Mexico (SSN-779). The author of ‘Execute Against Japan’: The U.S. Decision to Conduct Unrestricted Submarine Warfare (Texas A&M University Press, 2009), he holds a Ph.D. in history.