Ever since the weird little H.L. Hunly sank the USS Housatonic in Charleston harbour in July 1864, the submarine has been seen as a weapon of the weak, a ‘force-multiplier’ against a stronger adversary. In the eighteenth and nineteenth centuries, a skein of early inventors, Bushnel, Fulton, Nordenfelt and Holland all justified their efforts on this basis, very often with an over-mighty Royal Navy in mind. The stealth advantages of the submarine, they argued, would narrow the military-technical dominance the great navies derived from the capacity of their great ships to control the sea, to blockade the shipping of weaker countries, to seize their oversea possessions, to support land operations and even to threaten invasion. In the words of the French delegate to the 1922 Washington Treaty, ‘the submarine is the only arm that allows a country without a large navy to defend itself at sea’. 1
The experience of the First World War seemed to confirm all this. German U-boat operations seriously constrained the sea-control operations of the British Grand Fleet in the North Sea and its maritime power projection capabilities in the Mediterranean. Worse still from the perspective of the great navies, submarine operations seemed likely to transform the nature of maritime strategy itself by outflanking the classical emphasis on securing sea control as a precondition for all operational activity at sea. Instead, weaker navies equipped with submarines could achieve decisive strategic effect through a direct assault on the commercial shipping of the maritime powers. This moreover had major international repercussions, not least for its impact on US strategic thinking. 2 It was the same story in the Second World War, when Churchill rightly regarded the struggle against the submarines as the decisive battle at sea, at least in the Atlantic war. 3
At this stage, submarine technology was still mostly fairly primitive ‘and [submarines] could be described as torpedo boats capable of short periods of submerged operation’. 4 However, the advent of more sophisticated types like the German Type XXI pointed to numerous possible futures for the submarine. Indeed, when the US Navy initiated a major study of the possible functions of the submarine in the late 1940s, no less than 13 different roles that could be developed were identified.
In the Cold War, the military–technical pendulum seemed to swing even further in favour of the submarine and the significance of the undersea campaign, first because many so believed in the improving tactical advantage that stealthy long-endurance submarines had over apparently vulnerable surface ships that they simply divided fleets into 2 categories—submarines and ‘targets’. This was exemplified by the tremendous efforts the Royal Navy (one of the most skilled ASW operators in the world at the time) had to make in order to prosecute a couple of decrepit or malfunctioning and largely absent Argentine diesel submarines in the Falklands operation of 1982. Likewise, HMS Conqueror effectively checkmated the entire Argentine navy, after the sinking of the General Belgrano.
Second, submarines came into their own in two other ways as well. The deadly games played between the Russian and NATO submarines in Europe’s northern waters confirmed that they had become agents not just of sea denial, but of sea control, apparently usurping many of the functions of the old battle fleet. In the Second World War, British submarines sank 17 enemy submarines, and the Americans 24, but these were nearly all on the surface. At that time, the limitations in submarine sensors meant that submarine versus submarine operations under the surface were not yet a practicable proposition. Despite the scepticism of those who thought the submarine should stay focussed on fleet support, and in particular on guarding the carriers, technological improvements led to their assuming a central role in the general ASW battle. 5 In the post-war era, the submarine versus submarine battle became an essential—and indeed many thought the essential—dimension of the struggle for sea control. In this the nuclear propelled submarine had tremendous advantages over their diesel-driven equivalents in speed, range and endurance.
From the end of the Second World War, it also became increasingly clear that it was feasible for nuclear reactors to be installed in large submarines equipped to fire solid fuel ballistic rockets against the land. This all came to fruition in the USA with the cruise of the first SSN, the USS Nautilus in 1955, the commissioning of the USS George Washington, the first SSBN at the end of 1959 and the first firing of a guided Regulus I missile from the USS Halibut in the following year. 6 As the Soviet Navy’s Admiral Gorshkov repeatedly pointed out to sceptical colleagues in the Politburo, Army and Air forces, submarines were the ideal platform for the operation of the strategic nuclear deterrent and so seemed likely to make navies more strategically decisive than ever they had been before. The development of this mission inspired other roles for submarines too, in both the location and attack and defence of the SSBN ‘boomers’.
All these attributes of a well-handled submarine fleet seemed to mean that the development of a submarine capability could offer the navies of the Asia–Pacific region five different, but complementary kinds of potentially decisive strategic effect:
- Sea Denial & Control. Most obviously, their stealth and expanding offensive power, and their emerging role in ASW operations, made submarines a key element in battles for sea control between equal fleets and very possibly for the sea denial operations of a weaker fleet against a stronger one. The sinking of the ROKS Cheonan apparently by a mini-submarine of the North Korean navy suggests that even such unorthodox craft as these may have significant sea-denial potential, at least in some circumstances. This is important since such outcomes would effectively determine the shape of the subsequent conflict at sea, or even its likelihood in the first place. Given the current level of interest in anti-access/area denial (A2/AD) operations in the congested and contested littoral, all this would seem of particular interest to the navies of East Asia and the Western Pacific.For such war-fighting functions, the air-independent propulsion (AIP) systems gradually arriving in the region appears to offer major tactical and operational advantage since they allow the need to surface in order to recharge batteries to be reduced from perhaps once every 3–4 days to once every 2–3 weeks depending on how the submarine is used. Whether AIP proves to be one of those technologies that change everything remains to be seen, as does the particular form it might take and the relative attractiveness of the alternate route of going for improved Lithium-ion batteries instead.
- (Nuclear) deterrence. For some navies, submarines could become the principal and safest agents for the delivery, attack and protection of a country’s nuclear deterrent capability. For the moment at least, this would seem only of direct interest to a few of the larger navies of the region, but indirectly it could affect many others. The dynamics of the wider South China sea, for example, would be changed, for instance, should the Chinese seek to use it as a ‘bastion’ for their nuclear propelled ballistic missile- firing submarines (SSBNs) operations. It would increase still further the strategic significance of the area and China’s sensitivity to US naval activity there perhaps to plot the bottom, and to seed sonar buoys and other such listening devices. Likewise, North Korea’s determination to build up a substantial sea-based deterrent capability as evidenced by its recent missile firings, development of the Gorae (Sinpo) class of conventionally powered ballistic missile-firing submarines (SSBs) and the building of two large concrete submarine pens close to the Mayang-do naval base, has major implications, especially for the navies of South Korea and Japan.Neither should the potential attractiveness of non-nuclear deterrent effect potentially delivered by submarines be forgotten. Vietnam’s Kilo submarines, for example, are being upgraded in order to operate the Klub missile system which can be used against land targets. In some situations, this capability could add significant strategic effect to the general level of deterrence provided...