Can Japan defend the Senkaku Islands?

In the face of increasing Chinese incursions into its territorial waters and airspace over the past year, the defence of offshore islands in Japan’s southwest has become a pressing issue for both Japanese maritime policing and security policy. The Abe administration is scrambling to reform the institutional infrastructure of defence policymaking, revise defence policy and expand the operational capacities of the Japan Self-Defence Forces (SDF) and the Japan Coast Guard (JCG). Most recently, Japan and the United States have jointly decided to revise the Japan–US Defence Cooperation Guidelines to solidify the bilateral alliance. This takes up an idea first suggested by former Democratic Party of Japan (DPJ) Foreign Minister Seiji Maehara three years ago. A more controversial political decision on allowing Japan to exercise the right of collective defence remains in the wings.

Despite these prospective upgrades to both the alliance and Japan’s ability to defend its remote island territories, recent analysis by the former commander-in-chief of the Japanese Fleet, Yōji Kōda, highlights the glaring gap that remains in Japan’s defence of its maritime territory. He raises the possibility of a contingency in the Senkaku/Diaoyu Islands exposing the legal and operational limits on the JCG and the SDF successfully preventing and/or countering Chinese action to seize the islands by force.

The official duties of the JCG include ‘guarding territorial waters and the EEZ’, which involves marine surveillance and other activities such as dealing with the illegal operation of foreign fishing boats, intrusions into territorial waters and contiguous zones, and illegal landings of activists on islands. However, as Kōda points out, the problem here is that the JCG is a law enforcement agency and can only take action against private boats and civilians. It cannot use force against ships owned by foreign governments, such as Chinese Coast Guard or fisheries patrol vessels, or Chinese navy ships. Its actions are limited to ‘giving warnings and demanding their evacuation’.

As for the SDF, its activities are all grounded in domestic laws, including the SDF Law. Kōda argues that the legal authority for the Maritime Self-Defence Force (MSDF) to act in times of peace, before a defence mobilisation order (bōei shutsudō meirei) is issued by the prime minister and approved by the Diet, is limited. A defence mobilisation order can only be issued when Japan is under outside military attack or when there is a clear and imminent risk of an armed strike against Japan. Maritime security operations to protect assets and lives, and missions based on various special measures laws, fall well short of those authorised under a defence mobilisation order. The MSDF would have to fall back on the application, with necessary modifications, of the Police Official Duties Execution Law and the use of weapons for emergency evacuation and legitimate self-defence. In short, during peacetime, the MSDF cannot engage in the activities it was originally designed for as a national defence organisation, which leaves a huge gap in Japan’s maritime defence. In the event that a contingency escalates beyond the JCG’s capacity to act, the MSDF is authorised only to operate at the same or lower level of authority and use of force as the JCG.

These limitations pose problems for Japan’s defence of the Senkaku Islands. It would have difficulty, for example, in dealing with a scenario where Chinese special forces parachuted down on to the islands or landed from the sea using a submarine (the JCG’s patrol boats cannot deal with invasions from the air or underwater). The Chinese military could then take over the logistics of the landing in order to demonstrate China’s ‘recapture of effective control and establishment of sovereignty’ over the islands without shedding a single drop of blood or firing a single bullet.

The gap in Japan’s defence of its offshore islands is ripe for exploitation in the absence of an upgrade in the SDF’s capacity to deal with surprise attacks and the JCG’s air, sea and underwater surveillance capacities, as well as a mechanism for rapid government decision-making to deal with such a contingency. The establishment of a Japanese National Security Council will certainly facilitate much swifter government action, but recent media editorials in Japan also point to the need for territorial security legislation to enable the SDF to mount a defence of offshore islands short of full defence mobilisation. At present, it is possible, in the event of a Chinese surprise attack on the Senkaku Islands, for defence of the islands to fall in the grey area between what the JCG can deal with (non-military events) and what the MSDF is fully authorised to deal with (events for which a full defence mobilisation order can be issued). Contingencies in relation to offshore island defence would fall into this grey area. 

Japan’s fear of China’s forcibly taking and occupying the Senkaku Islands is not without foundation given unilateral Chinese action in relation to disputed maritime territories in the South China Sea. On the other hand, Japan’s stubborn adherence to its ‘there is no territorial dispute policy’ has excluded the opportunity for constructive bilateral negotiations between Japan and Taiwan and between Japan and China on this issue and indirectly encouraged direct action by both Chinese military and para-military forces. Amongst other things, this action has been designed to present the reality of a territorial dispute despite Japan’s official denials and Prime Minister Abe’s reassurances that ‘his door is always open to dialogue’.
Aurelia George Mulgan is Professor at the University of New South Wales, Australian Defence Force Academy, Canberra.