Exploring the Potential of an India-Japan Naval Treaty

15 Apr, 2020    ·   5676

Siddharth Anil Nair suggests that legal changes to the JSDF’s operational capabilities create conditions for a naval treaty that could operate as a powerful force in the IOR, IPR, and SCS

For decades, Japan’s military capability has been restrained by Article 9 of the Japanese Constitution. However, the introduction of two documents—the Guidelines for US-Japan Defence Cooperation (2015) (henceforth, the “Guidelines”), and Japan’s Legislation for Peace and Security (2016) (henceforth, the “Legislation”)—have expanded the conditions that allow for Japan’s use of force, and reduced the geographic limitations of the Japanese Self-Defence Force’s (JSDF) involvement beyond national waters.

This commentary will suggest that these two documents can inspire a potential India-Japan Naval Treaty that could help secure the Indian Ocean Region (IOR) and Indo-Pacific Region (IPR) against Chinese expansionism.

The Guidelines and the Legislation

The dynamic shift in the geopolitics of the IPR and the East and South China Seas (ECS; SCS)—courtesy of Chinese expansionism, North Korean belligerence, and US policy uncertainty—has expedited Japanese Prime Minister Shinzo Abe’s ambition to amend Article 9 of the Constitution. This is aimed at developing credible defensive capabilities independent of the US’ security umbrella.

The foundation of this ambition was laid down by the 2015 Guidelines, which broadened Japanese participation in US and other allies’ missions around the world by including mutual asset protection, logistical support, non-combatant rescue operations, etc. The February 2020 deployment of helicopter-destroyer Takanami to the Gulf of Oman is a direct consequence of this document. The ‘information gathering mission’ is operating far beyond Japanese waters, and in close proximity to the US-led naval protection operation in the Strait of Hormuz.

The 2016 Legislation was a result of parliamentary consensus, and includes new rules-of-engagement (RoE) for Japanese troops involved in UN peacekeeping missions, protection of Japanese nationals abroad, conducting ship-inspection missions, etc. The most significant change is the introduction of ‘Three New Conditions’ that determine the level of Japan’s military responses to attacks not only at home, but also in a “foreign country that is in a close relationship with Japan…” when it threatens Japan’s survival.

While still an “exclusively defence-oriented” policy, the changes instituted by the Guidelines and Legislation, along with increases in defence expenditure and power projection capabilities (such as the purchase of 147 F-35 A/B fighter aircraft and the reconfiguration of helicopter-carrier Izumo), allow Japan to manifest a proactive, independent geo-strategic posture vis-à-vis China. These qualitative changes are a bonus to Indian interests in the region, and offer a blueprint to take the joint India-Japan approach to the IOR and IPR, to a higher level.  

What Could an India-Japan Naval Treaty Look Like?

Both India and Japan uphold the principles of democracy, freedom of navigation, a rules-based order, and open trade. This is reflected in their “Security and Growth for All in the Region” (SAGAR) and “Free and Open Indo-Pacific Strategy” policies, respectively. These convergent principles have resulted in synergies in humanitarian aid/disaster relief (HA/DR) and maritime domain awareness (MDA) capabilities, while simultaneously encouraging joint-development of transcontinental infrastructure and economic partnerships in the IOR and IPR.

However, of serious concern today are the common Indian and Japanese threat perceptions of China’s naval and military build-up in these regions. Both India and Japan wish to develop adaptable and rapid responses to Chinese expansionism, and their main priorities are securing trade routes, oil supplies, and deterring Chinese incursions into sovereign territory. Their involvement in the US-India-Japan-Australia Quadrilateral, along with other trilateral initiatives, have been formulated to achieve these priorities. However, US policy uncertainty in the post-Trump era leads to the consideration of both India and Japan developing a security arrangement insulated from changing US priorities.

This arrangement could come in the form of a naval treaty based on existing bilateral convergences. Designing such a treaty now will be effective given the expansion in Japanese RoEs and its use of force. Official discussions on this subject, among other cooperative arrangements, have already gained momentum; in 2019, negotiations began for an Acquisition and Cross-Servicing Agreement (ACSA).

A potential naval treaty between India and Japan could be based on Sections A and B of the Guidelines, i.e. ‘Cooperative Measures from Peacetime’, and ‘Responses to Emerging Threats to Japan’s Peace and Security’ respectively. These two sections cover the mechanisms that determine cooperation in areas of intelligence/reconnaissance, air and missile defence, logistical support, training and exercises etc. The ‘Three New Conditions’ of the Legislation on the other hand could be extended to India and its interests in the IOR and IPR (given that the Diet approves of this extension). Further, the Japanese Defence Programs and Budget for 2020 outlines the need to improve cyber, space, electronic warfare, and ballistic missile defence (BMD) capabilities, which perfectly match India’s current capacity-building initiative in the maritime space, particularly submarine, surveillance, and BMD technologies.


While Chinese dominance in the region must be curtailed primarily through economic means—such as infrastructure, aid, trade, etc.—securing these interests calls for a comprehensive linkage of naval priorities as well. India-Japan maritime surveillance and BMD cooperation could lead to more tangible results than the informal Quadrilateral, or sole reliance on the US. The legal changes to the JSDF’s operational capabilities create conditions for a naval treaty between India and Japan, and based on a non-coercive principle of mutual security, such a treaty could operate as a powerful force in the IOR, IPR, and SCS.


Siddharth Anil Nair is a Research Intern with the South East Asia Research Programme (SEARP), IPCS.