Pranav Shah

“Strategic deterrence has been the sole mission of the fleet ballistic missile submarine (SSBN) since its inception in 1960. The SSBN provides the nation's [America’s] most survivable and enduring nuclear strike capability”[i]

This convincing sounding statement concisely summarizes the view that submarine-based deterrence is the “must-have” insurance policy for nuclear powers. While most agree that submarine based deterrence (in the form of Fleet Ballistic Missile Submarine-FBMS) has been a stabilizing influence in the difficult years of the cold war, some voice concerns that the FBMS is a costly and irrelevant option in the current and future geo-political context. These dissenting voices notwithstanding, at the present time, approximately 50% of the American strategic nuclear warheads are based on nuclear ballistic missile submarines (SSBNs).[ii] The large percent of warheads located on submarines clearly indicates the importance of SSBNs in the American nuclear doctrine. To understand why countries seeking security and regional stability would choose to develop a FBMS, one must examine the evolution of the American fleet ballistic missile submarines and their corresponding doctrine. Three documents, the Hearing before the Joint Congressional Committee on Atomic Energy, the Strat-X report, and the Congressional Budget Office’s Report concerning the Trident Missile Submarine, provide insight behind the reasoning for the development and the deployment of the SSBNs.[iii] In the next sections we examine each of these documents.

           The first key piece of evidence concerning the United States Navy and Congress’s rationale behind the development and the deployment of the first submarine ballistic missile, the Polaris missile, comes from the Hearing before the Joint Committee on Atomic Energy: Congress of the United States. The hearing took place on April 9, 1960 and a censored version of the transcript was declassified in May 1961. Senator Clinton P. Anderson presided over the hearing. One of the intriguing items about this hearing is that it took place on the nuclear submarine U.S.S. George Washington while it was at sea. This hearing was called so that the Senators and Congressmen could be briefed on the developmental progress of the Polaris missile, the first generation of submarine launched ballistic missile, and on the Navy’s nuclear propulsion program. Since this hearing took place before the first successful underwater launch of the Polaris missile, the testimony given indicates the envisioned role of SSBNs.[iv] Vice Admiral Hyman Rickover provided information on the nuclear propulsion aspect of the hearing, and Vice Admiral W. Raborn testified on the development of the Polaris missile. The Atomic Energy Commissioner John Floberg was also present.In those days the fear of a decapitating Soviet first strike dominated American thinking. The submarine was viewed as a nuclear-missile platform that was able to survive a first-strike because it was constantly moving and therefore very difficult to target with pre-emptive attacks. As Admiral Raborn states in his testimony,

“We are confident by moving [submarines armed with nuclear missiles] into the broad Atlantic and broad Pacific that we will leapfrog any countermeasures they [Soviet Union] may possibly dream up.”[v]

 The Admirals pointed out that since the Soviet Union could determine the exact location of land-based weapons, land-based weapons would be easy targets for a first strike. However, a submarine-based ballistic missile platform is mobile, and therefore would not be a good target for a nuclear missile strike. An excerpt from a Naval Message released by Admiral Burke on July 21, 1960 clearly illustrates the advantages of SSBNs:

“As Polaris-carrying submarines take their unknown stations throughout the world, the knowledge by the free peoples of the world—and those desiring freedom—that a Polaris submarine MIGHT be in the depths of international oceans, will give them additional determination to guard their freedom...This knowledge may even instill new confidence in those nations who have been threatened by aggression...[vi]”

This statement indicates that the U.S. Navy viewed its SSBN fleet as the force that would prevent a Soviet pre-emptive attack on the U.S. and its NATO allies. Furthermore, the naval message gives credence to the idea that the most-striking feature of the SSBN as a nuclear-weapons platform was that its precise location was unknown to the enemy.

There were also questions regarding the command and control of the submarines and their nuclear weapons were addressed. Admiral Raborn pointed out that the Navy had high and low frequency stations that were be able to send messages to the submerged submarines, and thus were capable of issuing launch orders. He assured the Congressional members that “you can send messages to submerged submarines...with assurance 365 days a year.”[vii] Clearly, the Navy viewed the deployment of the SSBN submarine with great confidence because it assured American retaliatory capability and guaranteed safety.

          As the Hearing Before the Joint Committee on Atomic Energy indicated why the U.S. developed the ballistic missile submarine in the first place, the Strat-X Report indicates why the American government felt that SSBN would be continue to be a necessity. In addition, the document gives further insight into the American FBMS doctrine. Secretary of Defense Robert McNamara commissioned the Strat-X study on November 1, 1966 to “characterize U.S. alternatives to counter the possible Soviet ABM deployment and the Soviet potential for reducing the U.S. assured destruction force effectiveness during the 1970s.”[viii] The significance of this study lies in its thoroughness and in its clear articulation of the basic requirements for a survivable nuclear weapons platform. The study considered 125 different ballistic missile platforms, and thoroughly explored the design, the reaction, the nuclear effect, the cost, and the payload of various platforms and missile systems.[ix] The full report consisted of twenty volumes of analysis with each volume consisting of approximately a hundred pages. Additionally, the classification level of this report underlines its importance in formulating the American nuclear doctrine—it was classified “Top Secret” with only 125 copies of the report printed. Furthermore, many pages of the report were “sanitized” or censored by the requirements of the Atomic Energy Act.[x]

          The report’s first volume begins by outlining the scope of the study. Strat-X evaluated the ballistic-missile launch locations on their design, cost, implementation, and survivability of the location.[xi] The report states that the primary factor by which the nuclear-missile platforms were judged was survivability. Five design features--hardness, decoy aimpoints/deception, active defense, mobility, and concealment--were identified as giving a platform more survivability.[xii] Of the many platforms, nine missile systems were studied in detail: rock silo, soft silo, rock tunnel, soft tunnel, canal based, land mobile, ship based, submarine based, and air launched ICBM.[xiii]

Even though some pages of the Strat-X report are censored, many statements give indication about the direction and the conclusion of the report. The report’s first volume, the summary volume, states that the Soviet Union would most likely react to increased Minuteman missiles and building of Rock Silos by fielding missiles with maneuverable re-entry vehicles and sophisticated penetration aids.[xiv] Additionally, the report postulates that the Soviet reaction to increasing the range of the submarine launched ballistic missile would be to create an “aircraft laid sonobuoy field and depth-charge attack” that would attempt to destroy all submarine contacts. However, the report continues, the size of this reaction force is completely dependent on the available ocean operating areas of the submarine. An increase in the patrol area as planned for the “New Submarine” would force a ten-fold increase in the number of aircraft, sonobuoys and depth charges required to reduce the overall survivability of the SSBN fleet.[xv]

          The report then discusses the conclusions that the committee reached concerning Land-Based Mobile and Ship-based nuclear missile platforms. The report states that the most-probable Soviet reaction to land-based mobile missiles would either be a “barrage bombardment of the operating area [of the land based mobile system]” or an attack with sophisticated missiles whose multiple warheads were guided to the launcher by a satellite tracking system.[xvi] A ship-based system, the report concluded, was vulnerable to a large raid with bomber-type aircraft.[xvii]

          The Strat-X report argues that the assured retaliation and destruction capabilities can be achieved only by platforms that are likely to survive a surprise attack. This requires that the platform be able to deny real-time information about its location to the enemy; in other words, the platform must be undetectable for long periods of time.[xviii] Because of this, one can assume, since some of the pages are censored, that the report recommended the development of the “new submarine.” The new submarine refers to a submarine with an increased patrol range containing ballistic missiles with superior range. These two factors would enlarge the area of ocean that it could patrol. Essentially the submarine’s ability to perform “silent service” had once again made it indispensable. We now examine the third document of significance.

The third document, The U.S. Sea-Based Strategic Force: Costs of the Trident submarine and Missile Programs and Alternatives, was prepared in 1980 at the request of the Senate Committee on Armed Services to determine the long-term cost-effectiveness of the Trident submarine force.[xix] The National Security and International Affairs Division of the Congressional Budget Office prepared the paper. Additionally, since the Congressional Budget Office published the paper, the paper offers no recommendation as the Budget Office is mandated to provide “nonpartisan and objective analysis.”[xx]

          This report echoes the concern of the previous two documents regarding the importance of the survivability of a nuclear weapons platform. The paper argues that the Trident submarine force would be more survivable because the Trident submarines can carry more missiles compared to older Poseidon class SSBNs. As a result, the total number of submarines required to maintain the same number of missiles would be smaller. Since, the submarine fleet would be smaller, it would be harder to locate and more like to survive.[xxi] The paper explicitly delineates some of the advantages of SSBNs. The first advantage mentioned is that a Soviet attack on American strategic forces would be unable to destroy any SSBN at sea because the “the Soviets’ ability to locate and destroy U.S. SSBNs is believed to be extremely limited.” Hence, the SSBN would survive the first-strike and be ready for retaliatory action. Therefore, the paper concludes, SSBNs are a “significant” deterrence against a pre-emptive attack on American nuclear forces.[xxii]    The paper also states that SSBN’s “independence from tactical warning” is a significant asset. In other words, the SSBNs require no warning of imminent attack in order to survive. This is unlike land-based bombers, which require a warning of impending attack so that they can be airborne and escape attack.

Additionally, the paper argues that the SSBN’s self-sufficiency after surviving a nuclear strike is another major benefit. Bombers and land-based missiles, if they survived the initial strike, would have a limited time to launch their missiles. A bomber can only stay aloft so long; and once the Soviet military realized that there were land-based missiles still not destroyed, they would launch another smaller strike aimed at destroying the remaining warheads. However, SSBN has much better chances of survival in the open sea and is only limited by food supply and crew endurance. Hence, the U.S. would have an increased amount of time, from days to weeks, in which to plan a response because the leadership would be assured that all their strategic warheads would not be destroyed.[xxiii]The paper summarizes that the SSBN are valuable for crisis stability. As their mere presence assures a retaliatory strike,[xxiv] in a crisis the act of bringing the SSBN fleets to a high state of alert serves to remind the adversary of this fact and deters nuclear adventurism.

          The study then considers various threats to the SSBN fleet posed by possible Soviet tactics. For example, the paper points out that a Soviet strategy of tracking or “trailing” all the SSBNs at sea is likely to be very unsuccessful. There are several factors that would make this strategy futile. The first is that the SSBN’s patrol cycles and patterns are staggered. Hence, the SSBN would have to be tracked over several weeks in order to determine its patrol pattern. This task is further complicated because the SSBN must be tracked in such as manner that the SSBN is unaware of being shadowed. If the SSBN became aware, it would notify higher command, and the U.S. would be able to take step to preserve its SSBN force.[xxv] It appears from this that the United States Congressional Budget office and the Senate confirmed the arguments in favor of the FBMS.

          Based on these documents the American government’s rationale to deploy SSBNs can be summarized as follows. The SSBN platform is most immune to surprise attacks aimed at destroying American strategic forces, it is also capable of operating with enormous endurance and independence. It therefore constitutes a survivable and credible second-strike capability.

          Many other nations came to the same conclusion. Since the U.S. deployment of submarine-based deterrence, Russia, Great Britain, France, and China have followed suit. Russia has over 50% of the deployed strategic weapons at sea; France has over 80% of its strategic weapons, and Great Britain has all of its strategic weapons on submarines.[xxvi]  It seems plausible that other nations may also find this path attractive.Some argue that SSBNs are not relevant to current geo-politics because only a few nations posses nuclear weapons, and of those, only a few, like the U.S., Great Britain, France, China, Russia, can afford to develop, build, and maintain SSBNs.

 While the view that the cost deters most nations from developing and deploying SSBNs is true, it must be borne in mind that “cost” is a relative concept. India, for example, with its complicated deterrence requirements has to plan for the possibility of a strike aimed at destroying their strategic forces. As the “cost” of losing its strategic forces to “decapitating” or “debilitating’” nuclear first strike is unimaginably high, India too seeks a weapons system that can project a guaranteed second-strike capability. FBMSs appear to be such a system. As far as India is concerned, “the SSBN offers a viable, robust and credible deterrence posture… the versatility of an SSBN leaves little choice before strategic planers but to concentrate on sea based deterrence.”[xxvii]  India is thus in the process of developing its own SSBN.[xxviii] Given Pakistan’s tendency to copy Indian actions a similar approach may emerge albeit in recessed form in Pakistan as well.[xxix]