[PDF version] (The article appeared originally in Japanese in IIPS Quarterly, dated November 9, 2015).

In April 2015, a new set of Guidelines for US-Japan Defense Cooperation ("the new guidelines") was established. Because the guidelines are not legally binding, domestic legislation must be passed in both countries to ensure their effectiveness. In September 2015, the Japanese legislature passed a series of bills relating to security, making security legislation consistent with the new guidelines. There are certain aspects of the new guidelines that have already been widely debated. This paper will discuss the new guidelines as they relate to the maritime strategy of the US, a topic that has not received much attention. It can be inferred that deliberations about maritime strategy at the service-branch level and about the amended guidelines were conducted more or less concurrently by defense-related organizations in the US, as the latest maritime strategy at this level was released one month before the guidelines, in March 2015.

The New US Maritime Strategy
In March 2015, the US updated its maritime strategy, "A Cooperative Strategy for 21st Century Seapower" (referenced below as the "2015 maritime strategy"), for the first time in eight years. This maritime strategy was issued jointly by the Navy, the Marines, and the Coast Guard, and it serves as strategy at the level of these three branches. Within the framework of US security strategy, this document is considered subsidiary to the National Security Strategy and the National Defense Strategy, which are formulated, respectively, by the president and the secretary of defense, as well as to the National Military Strategy and the Quadrennial Defense Review (QDR), which are drafted by the Joint Chiefs of Staff.

All major strategy-related documents that the US Navy has issued, including the 2015 maritime strategy, have sections describing the Navy's mission; how each document defines this mission provides a succinct characterization of the document. The 2015 maritime strategy lists five "essential functions" of the so-called Sea Services (maritime military branches): all-domain access, deterrence, sea control, power projection, and maritime security. All but the first of these essential functions are described as having been performed throughout the branches' histories. In fact, the four items that have been consistently described as missions or essential functions in major documents issued since the end of the Cold War are deterrence, sea control, power projection, and forward presence; the term "maritime security," as an essential function, first appeared in the previous 2007 maritime strategy.

The 2015 maritime strategy was the first such strategy--since the Cold War or, indeed, ever--to expressly list all-domain access as a function of the US Sea Services, and this is arguably a crucial feature of the document. The term "all-domain access" refers to projecting military force into the sea, air, land, space, cyberspace, and electromagnetic spectrum to secure freedom of action. The 2015 maritime strategy explains that the concept was introduced "because access to the global commons is critical." The 2015 maritime strategy removed from this list the concept of forward presence, which until then had consistently been considered a crucial function. It is likely that this omission is due to "forward presence" meaning the ability to deploy maritime forces forward in both peacetime and wartime; the concept is thus included within all-domain access.

The 2015 maritime strategy posits two "foundational principles": (1) forward naval presence and (2) joint operations with allies and partners. The two principles are closely linked. Forward presence, which provides the capacity for forward deployment of maritime forces, entails the costs of moving resources from home ports and bases, many of which are located on the US mainland. To balance the two goals of minimizing these costs and increasing the US naval presence, the 2015 maritime strategy proposes increasing the number of forward bases for overseas units. Without the second foundational principle of joint operations with allies and partners, it would be difficult for presence-enhancing measures, such as increasing the number of overseas bases, to deliver effective results. Hence, the 2015 maritime strategy states that the US will promote a global network of navies by "deepening security cooperation with allies and partners." For these forward-deployed units to operate effectively, it will be essential to enhance allies' and partners' own capabilities, as well as to improve interoperability between their forces and US forces.

The Guidelines for US-Japan Defense Cooperation from the Perspective of US Maritime Strategy
Based on the 2015 maritime strategy, the new guidelines are crucially significant in the following ways:

First, the new guidelines added provisions for the Japan Self-Defense Forces (JSDF) and the US military to conduct joint cross-domain operations in the event of an armed attack against Japan. The phrase "cross-domain operations" is arguably representative of broader US strategic thinking in recent years.

The AirSea Battle (ASB) concept--which was redubbed the Joint Concept for Access and Maneuver in the Global Commons (JAM-GC) in 2015--is intended to maintain access to the global commons and ensure freedom of action in environments subject to anti-access/area denial (A2/AD) measures. The concept also attempts to maximize its strategic benefits by not merely conducting joint operations but also conducting them across all domains--the sea, air, land, space, and cyberspace. The concept also posits that it is necessary to conduct cross-domain operations spanning all the domains listed to realize the central concept of the doctrine: "networked, integrated, and attack-in-depth operations."

Considering that the 2015 maritime strategy introduced the new concept of all-domain access, the fact that the new guidelines expressly state that Japan and the US are to conduct cross-domain operations jointly would seem to mean that the JSDF is one of the two pillars of a major US military strategic concept. The US Navy has stated that joint operations and interoperability with allies and partners are even more crucial when deploying forces for JAM-GC in order to guarantee friendly actors access to, and freedom of action in, the global commons. It would also seem to indicate that the US expects much from Japan, given that the 2015 National Military Strategy lists Japan as one of the countries that are "advanced partners" whose "sophisticated capabilities such as assuring access to contested environments" the US military will focus on in joint exercises.

The second way in which the new guidelines are significant is their inclusion of a section on "Space and Cyberspace Cooperation" and provisions for Japan and the US to cooperate to guarantee the ability to use both domains. As is implied by the broadness of the term, the US military emphasizes both outer space and cyberspace when it lists all-domain access as an essential function. Thus, Japan and the US will continue to make strides in defense cooperation with the aim of the stable use of space and cyberspace--two domains that the US emphasizes as parts of the global commons.

The third item of note is that, as a result of the recent international situation, the new guidelines introduce mention of cooperation in the area of maritime security, which is a significant issue for Japan and the US. The previous guidelines did not contain anything related to maritime security. By contrast, the new guidelines stipulate that Japan and the US will closely cooperate to preserve maritime order during peacetime, as well as to enhance maritime security as part of "responses to emerging threats to Japan's peace and security." The new guidelines also mention maritime security in relation to cooperation for the peace and security of the Asia-Pacific region and of the globe as a whole. Japan-US cooperation is particularly crucial when it comes to activities in the Asia-Pacific region such as partner capacity building, intelligence, surveillance, and reconnaissance.

Finally, the new guidelines have geographically expanded the range in which the JSDF will be active. One way in which the guidelines do this is by stating explicitly that the Japan-US alliance will "respond to situations that will have an important influence on Japan's peace and security" and that "such situations cannot be defined geographically." In addition, the guidelines have enhanced the functioning of the Japan-US alliance even in cases that are not as dire as an armed attack against Japan. For instance, a provision of the guidelines states that, when "an armed attack against a foreign country that is in a close relationship with Japan occurs," the JSDF will, under certain conditions, "conduct appropriate operations involving the use of force." These changes to the role of the JSDF will mean greater flexibility for the US military in global-scale operations, enabling the US military to enhance its worldwide presence. Thus, the revised, new guidelines were a critical update with significant implications for US maritime strategy.

(The views expressed in this paper are those of the author as an individual and do not necessarily represent the views of any organizations to which the author belongs.)