In December, the Japanese Defence Ministry released the much-anticipated National Defense Programme Guidelines (NDPG) 2010. The NDPG identifies Japan’s off-shore islands as a new priority for defence planning, and advocates shifting the nation’s strategic focus to the East China Sea and Japan’s southern Ryukyu Island chain. Although it doesn’t specify how it will accomplish this, the combination of land, air, and sea-based capabilities called for in Japan’s Mid-Term Defense Programme (2011-2015) budget document suggest Tokyo aims to adopt an area-denial strategy for defending its off-shore islands.
The geographic position of the Ryukyus to China’s first island chain, combined with the modernization and more assertive posture of China’s People’s Liberation Army Navy (PLAN), have demanded that Japan take steps to enhance its deterrence in the region. Along with the flashpoint of the Senkaku/Diaoyu islands, the geographic location of the Ryukyu Island chain all but guarantees friction between Japan and China.
The islands stand as an archipelagic border along the northern portion of China’s first island chain through which Chinese naval and commercial vessels must pass on their way to the Pacific Ocean. Also, the proximity of the Ryukyus to Taiwan ensures that the islands would play an operational role in any conflict. When considered alongside the PLA Navy’s growing strength, it’s not difficult to imagine why these seemingly inconsequential islands have become affixed in the minds of Japanese strategists.
If Japan is pursuing an area-denial strategy it would have two tiers. First, it would be able to detect and hold at risk mobile targets in the oceanic ‘blue water’ approaches to the Ryukyus. Second, it would defend against amphibious manoeuvres in the ‘green water’ of the littorals. Japan’s procurement plans appear serious about enhancing the SDF’s capacity to do the first, while carefully beginning to build up the capabilities necessary to achieve the second. As this approach matures, Japan should forgo seeking parity with PLA forces in favour of an asymmetric approach that considers how it can exploit the various military and geographic advantages available.
A Japanese area-denial strategy first seeks to control the surrounding sea and air space of the East China Sea. This requires building an accurate picture of the maritime environment and retaining the capacity to conduct sea-control operations. The Mid-Term Defense Program gives priority to expanding continuous steady-state intelligence, surveillance, and reconnaissance (ISR) capabilities. This includes deploying ground-based surveillance radars to the Ryukyus, developing a maintenance infrastructure to support aircraft in the region and expanding the fleet of maritime patrol aircraft. In addition, Tokyo’s plan to procure new helicopter destroyers, destroyers, submarines and a new maritime patrol aircraft will allow it to protect vital sea lanes in the areas surrounding the Ryukyu archipelago.
The second tier of a Ryukyu area-denial strategy rests in the green waters of the littorals where Japan aims to defend against hostile naval patrols and amphibious manoeuvres that could threaten its territory. Here, the NDPG has begun to initiate a considerable shift in Japan’s defence posture. Most significantly, it directs the deployment of Ground Self-Defense Force (GSDF) units to the southern islands for surveillance missions and stands up new units designed for rapid deployment contingencies in the region. It also calls for procurement of ground-based anti-ship missiles and surface-to-air missiles to be stationed on the islands.
The new capabilities called for in the NDPG represent a shift in Japanese defence thinking towards the region. However, this approach remains in its infancy. First, Japanese defence planners will have to consider how they can integrate their land, air, and sea-based capabilities as part of a networked area-denial force.
Second, the 2013 review of the NDPG would be a good opportunity for the MOD to investigate how Japan can exploit asymmetric advantages that could impose greater costs on PLA forces. For instance, it could develop an integrated and dispersed network of fast attack ships, mine warfare capabilities, diesel attack submarines, shore-launched missiles, and tactical aircraft. Finally, Japan and the United States will have to explore what role the alliance can play in enhancing deterrence and defence missions in the region.
The value of an asymmetric approach is that it would allow Japan to avoid the hefty costs of seeking to match PLA Navy investments while also freeing-up expensive surface combatants for other missions like sea lane defence. Because Japan’s stagnant defence budget, the growing cost of military platforms, and the aftermath of the Tōhoku earthquake and tsunami will only continue to force uncomfortable realities on defence planning in Tokyo, unorthodox thinking like this should be encouraged as its Ryukyu area-denial strategy matures.