Elements of the First Marine Division and the Japanese 2nd Amphibious Rapid Deployment Regiment Landing Team have demonstrated the growing interoperability and joint warfighting capability of the US and Japan’s developing marine units, shedding light on Japan’s continued shift away from its pacifist constitution.
Japan has closely followed the modernisation of the Chinese armed forces and raised concerns about the nation’s defence capabilities and the continued relevance of the post-Second World War, pacifist constitution.
As a result, the Japanese government has responded with a period of unprecedented defence budgets as the pre-war power seeks to shake off the chains of the pacifist constitution enforced upon it by the US, UK, Australia and other allies following the end of the war in the Pacific.
Growing Chinese assertiveness in the South China Sea and modernisation efforts resulting in the fielding of key power projection capabilities, including aircraft carriers and supporting strike groups, fifth-generation combat aircraft, modernised land forces, area-access denial and strategic nuclear forces, combined with growing political and financial influence throughout the region, is serving to shake Japan's confidence.
Accordingly, Japanese Prime Minister Shinzo Abe has repeatedly earmarked increased funding for the nation's defence budget, expanding the capabilities of the Japanese Self-Defense Forces (JSDF).
Prime Minister Abe has long been suspected of harbouring plans to repeal the post-Second World War constitutional limitations, namely Article Nine, and reinstate a power projection focused force structure and doctrine to be supported by Japan's industrial capability to modernise and equip itself in the face of growing regional instability and tensions.
Amphibious warfare operations and doctrines have emerged as a key focus point of Prime Minister Abe's long-term restructure and reorientation of the JSDF. In recognising this, the Japanese have stepped up frequent interoperability and training operations with the US Marines and Australia's own developing amphibious units.
Most notably, Japan's 2,100-strong Amphibious Rapid Deployment Brigade (ARDB) participated with the other regional allies as part of Exercise Talisman Sabre 2019 to perfect contemporary amphibious operations.
Major General Roger Noble, Deputy Chief of Joint Operations for the Australian Defence Force, clarified the importance of amphibious operations and Australia's commitment to evolving the capabilities, in conjunction with partners like Japan, saying:
"Australia’s defence policy continues to be based on the three interconnected strategic interests of a secure, resilient Australia, with secure northern approaches and proximate sea lines of communications; a secure nearer region, encompassing maritime south-east Asia and south Pacific; and a stable Indo-Pacific region and rules-based global order."
Building on this example, Japan's 2nd Amphibious Rapid Deployment Regiment Landing Team have joined elements of the US Marines First Marine Division, based at Camp Pendleton, California, to participate in Exercise Iron Fist 2020.
Developing doctrine and CONOPS to support a "separate but synchronised" capability
Drawing on the example set by US Marine forces based in and around Japan, the island nation has moved rapidly to enhance the 2,100-strong ARDB concept as part of the broader “south-western wall” to serve in a similar function to that of China’s A2/AD network.
That is to blunt any potential adversary’s concerted naval and aerial attack through the use of integrated anti-ship and anti-air defence systems, combined with roving packs of hunter-killer submarines, airborne early warning, command and control aircraft, fighters and, in the event of an amphibious occupation, the ARDB.
Additionally, it is envisioned that Japan's ARDB unit will serve as a quick reaction force capable of securing Japan's far-flung territorial holdings, particularly those islands closer to the Chinese mainland that have served as contentious flash points between the two major powers.
As part of developing this capability, the joint training exercise provided an opportunity for both forces to develop what Captain Coleman Fuquea, a US artillery officer and exercise planner with the 15th Marine Expeditionary Unit, describes:
"We wanted to pursue the concept with them of 'separate but synchronised', so headquarters and staffs working together and synchronising. But on the tactical level, US and our Japanese allies would fight in separate battle spaces."
Building on this, the ARDB units joined their Marine counterparts and spent several weeks training prior to launching the amphibious landing operation, which included landing on a defended island, with the Japanese force serving as a defending, or Opposing Force (OPFOR), keeping the nation in line with the Japanese constitution.
Capt Fuquea explained, "The scenario is the seizure of an island, built into our larger scenario."
This was reinforced by the US Naval Institute, which expanded on the focus of Exercise Iron Fist 2020, stating: "The Japanese force wasn’t training to seize an island – Japan’s constitution prohibits offensive military operations – but rather is building and strengthening its capabilities for maritime security, including defending islands from an invading force.
"The scenario is a real and ongoing threat to Japan, an island-nation whose 3,000-plus islands include contested claims by China and other countries, including the disputed Senkaku Islands in the East China Sea."
Plans to integrate Japan's growing maritime power projection capability
Japan's ARDB unit is to be supported by the rapidly developing naval-based power projection capability, including the Izumo and Hyuga Class vessels to replicat the compact, yet highly-capable force structure of the joint US Navy/Marine Expeditionary Strike Groups.
Japan has initiated a range of modernisation and structural refits for the Izumo Class vessels to develop small aircraft carriers capable of supporting airwings of 28 rotary-wing aircraft, with capacity for approximately 10 'B' variants of the F-35 Lightning II Joint Strike Fighter, with both 27,000-tonne vessels capable of supporting 400 marines.
The smaller Hyuga Class vessels, weighing in at 19,000 tonnes, are capable of supporting an air wing of 18 rotary-wing aircraft, with space for amphibious units and supporting equipment. Additionally, it is speculated that like their larger Izumo Class cousins, the Hyuga and sister Ise can be modified to accommodate the F-35B.
The introduction of these capabilities will directly support Japan's long-range maritime strike, air interdiction and fleet aviation capabilities, which are critical to defending Japanese territorial and economic interests in Indo-Pacific Asia.
These vessels, in conjunction with smaller Osumi Class transports, will also play host to the Japanese Ground Self-Defence Force's (JGSDF) ARDB.
These serve as a promising addition to future training operations and CONOPS development for both the US and Japanese forces, something highlighted by Capt Fuquea, who added, "It would be great in the future if we could get a Japanese L-class ship here. What we’d really like to see in the future is force-on-force training and have the US and the Japanese more of a sparring-partner relationship. That allows unit leaders … to get a thinking adversary."
Developing complementary force structures
The Australia-Japan relationship is the nation's closest and most mature in Asia and is underpinned by the strategic, economic, political and legal interests of both countries. The countries work closely in strategic alliance with the US, and lead in critical regional partnerships with countries such as India and the Republic of Korea.
Australia and Japan regularly participate in joint defence exercises and frequently consult on regional security issues, such as the nuclear tests and ballistic missile launches undertaken by North Korea.
The Joint Declaration on Security Cooperation (JDSC) signed in 2007 provides a foundation for wide-ranging co-operation on security issues for both countries, including law enforcement, border security, counter terrorism, disarmament and counter-proliferation of weapons of mass destruction.
The JDSC also established the regular 2+2 talks between the respective foreign and defence ministers.
Like Australia, Japan is dependent upon unrestricted access to critical sea lines of communication (SLOC), which require robust naval and air power capabilities –these developments and the strategic reorientation provides avenues for the two nations to develop similar, complementary force structures to ensure unhindered access to Indo-Pacific Asia's SLOC.
For both Australia and Japan, nations defined by their relationship with traditionally larger, yet economically weaker regional neighbours, the growing economic prosperity of the region and corresponding arms build up, combined with ancient and more recent enmities, competing geo-political, economic and strategic interests, places the nations at the centre of the 21st century's 'great game'.
Further compounding the precarious position of the two US allies is the need to accept that 'Pax Americana', or the post-Second World War 'American Peace', is over and Australia and Japan will be required to develop unique national responses to defend their unique national interests, with a focus on supporting the key alliances.