Earlier this summer, the Australian and Japanese militaries conducted the naval exercise Trident 2023 in the South China Sea, as part of increasing cooperation between the two democratic nations. The image of a two-nation bloc patrolling in the waters together will send a unified message to China, which maintains a continual presence of hundreds of warships across the South China Sea to assert its claims in the area.

The drill was part of the Japan Maritime Self-Defense Force’s Indo-Pacific Deployment 2023. It was carried out by helicopter destroyer JS Izumo (DDH-183) and destroyer JS Samidare (DD-106), along with the Royal Australian Navy frigate HMAS Anzac (FFH150) and a Royal Australian Air Force P-8A Poseidon Maritime Patrol Aircraft (MPA) in the South China Sea. It emphasized tactical operations such as anti-surface and anti-air warfare.

The war games, which took place in strategically disputed waterways, focused on tactical operations such as anti-surface and anti-air warfare. Following a port call to Vietnam as part of an Indo-Pacific Deployment, the two warships from the JMSDF participated in the bilateral training maneuvers.

The relationship between the Japan Maritime Self-Defense Force (JMSDF) and the Royal Australian Navy (RAN) has never been stronger or more important, and the JMSDF will work with the RAN on interoperability and mutual understanding in order to improve the security environment in the Indo-Pacific region.

Tokyo and Canberra’s bold Indo-Pacific strategies

The exercise is critical for continued strategic collaboration between Japan and Australia in the region and offers substantial strategic potential for promoting Indo-Pacific multilateralism. Australia and Japan regard each other as special strategic partners in the Indo-Pacific area. The two democratic nations share not only core principles but also strategic interests in a region increasingly threatened by China, which claims large portions of the South China Sea as its own territorial waters.

Japan and Australia vowed to oppose any unilateral attempts to change the status quo by force in the East and South China seas, a veiled allusion to Beijing’s maritime aggression there. Japan and Australia vehemently oppose China’s claims and activities that violate international law and norms, notably the United Nations Convention on the Law of the Sea. Against such a backdrop, the joint military drill will improve the partners’ combined ability to maintain maritime security and readiness, as well as respond to any regional contingency. 

Fumio Kishida and Australian Prime Minister Scott Morrison signed a bilateral reciprocal access agreement (RAA) in January 2022 to facilitate mutual troop deployment to each respective country for joint drills and relief operations. The RAA is Japan’s second official defense treaty with another country, confirming Australia’s position as the country’s second most significant security partner behind the United States, Japan’s only treaty ally. 

Japan’s Prime Minister Fumio Kishida debuted the new “Future of the Indo-Pacific” strategy during last year’s Shangri-La Dialogue in Singapore. In a word, the new strategy represents Japan’s concept of global responsibility. According to Kishida, Japan wishes to offer “a guiding perspective” for a world on the edge of “division and confrontation.” Japan’s “free and open Indo-Pacific” strategy, as it has expressed through the Quadrilateral Security Dialogue (or Quad), has grown in significance since 2016.

Japan has announced a significant increase in defense spending, which it aims to use to strengthen offensive capability platforms and counterstrike capabilities. Japan will spend $324 billion over the next five years to bring itself up to par with NATO expenditure standards. Japan has already upped its defense budget to $51.4 billion in the 2023-2024 fiscal year, a 26% jump from the previous year. Japan wants to purchase long-range missiles like Tomahawks, among other things, to improve its strike capability.

Australia too has outlined a more assertive defense posture in which the country will prioritize new technologies, such as maritime and long-range strike capabilities. In a declassified version of its new defense strategic review—the most significant in over 40 years—Australia determined that it must “re-posture,” since it is no longer as shielded by geography and other nations’ limited ability to project power. The country is set to spend an eye-watering $368 billion ($240 billion in US dollars) on nuclear submarines over the coming years. 

Australia’s priority is to strengthen its involvement and collaboration with Southeast Asian and Pacific allies in reaction to China’s rising assertion of sovereignty over the South China Sea and the danger that poses to the global rules-based order.

Japan and Australia part of a broader defense network

Military preparedness in the region has been ramping up. Japan and Australia are not expanding their military spending and cooperation in a vacuum. Both are close allies of the US, which has also increased its involvement in the region by signing the General Security of Military Information Agreement with Japan and India as well as the AUKUS treaty with the UK and Australia. AUKUS aims to significantly strengthen Australia’s maritime capabilities with nuclear-powered submarines. The allies revealed the terms of the accord in March 2023, which included a second pillar on advanced technical exchange and force integration, as well as a substantial new role for AI-enabled platforms.

China, too, has deepened its involvement, for example by ramping up incursions into Taiwan’s Air Defense Identification Zone.

China, Taiwan, the Philippines, Brunei, Malaysia and Vietnam all claim areas of the disputed South China Sea. Beijing has constructed artificial islands and military outposts in the waters and has experienced similar conflict with Japan in the East China Sea.

The South China Sea has become a theater of strategic rivalries, especially following the Russia-Ukraine War and the crisis over Taiwan. The Indo-Pacific partners are jointly conducting military deals to counter the Chinese maritime ambitions called the “string of pearls.”

Professional engagement and collaboration with friends and partners are the bedrock of regional stability, which promotes peace and prosperity for all nations. The USS Momsen (DDG 92), an Arleigh Burke-class guided-missile destroyer, joined the JMSDF and the RAN in the South China Sea for multinational training that was completed on March 15. The coastguards of the United States, Japan and the Philippines, too, are cooperating in maritime exercises in the South China Sea, marking the first such maneuvers between the three nations.

Hence, Japan-Australia’s joint military exercise is part of a broader movement of cooperation between China’s neighbors, which are feeling the pressure of Chinese expansion. They aim to defend freedom of navigation in favor of a free and open Indo-Pacific. The Trident exercise and others like it, however, will also deepen regional tensions as China will be incensed by what it perceives as aggression in its backyard. Whatever happens, we can expect to watch increasing militarization in the region for the foreseeable future.

[Anton Schauble edited this piece.]

The views expressed in this article are the author’s own and do not necessarily reflect Fair Observer’s editorial policy.