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The Australia-Japan-US Trilateral: Forming Collective Deterrence in the Indo-Pacific

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The Australia-Japan-US Trilateral: Forming Collective Deterrence in the Indo-Pacific

Any direct deterrent contribution – meaning participation in high-end military operations – will arguably stem from these long-standing and increasingly united U.S. allies.

The Australia-Japan-US Trilateral: Forming Collective Deterrence in the Indo-Pacific

U.S. Air Force members, Palau International Fire members, Royal Australia Air Force members and Japan Air Self-Defense Force members pose for a photo at Palau International Airport, Palau, Feb. 14, 2023.

Credit: U.S. Air National Guard photo by Senior Airman Christa Anderson

The Russian invasion of Ukraine and the violent conflicts in the Middle East remind the world that war is the rule rather than the exception. Deterring another bloody war is doubtlessly more critical than ever, especially in the Indo-Pacific, which has several flash points. Former Japanese Prime Minister Kishida Fumio summarized this well by noting repeatedly “Ukraine may be the East Asia of tomorrow.” 

Deterrence in the Indo-Pacific is arguably achievable if collective efforts sustained by regional countries are well managed, as U.S. Defense Secretary Lloyd Austin suggested. This collective approach to deterrence is enabled by trilateral efforts among the United States, Japan, and Australia. These countries are increasingly more united and even committed to working together for regional defense and deterrence. Such commitments can be seen through formalized Trilateral Defense Ministerial Meetings and their investment in next-generation military drones, long-range missiles, and missile defense systems. Furthermore, any direct deterrent contribution – meaning participation in high-end military operations – will arguably stem from those long-standing U.S. allies.

It is clear that countries in the Indo-Pacific are growing more concerned about China’s coercive acts in the region, and they have started to address this challenge in different ways. The formation of AUKUS (the security partnership among Australia, the U.K. and the U.S.) and the recent promotion of the Squad (an emerging quadrilateral group among the U.S., Japan, Australia, and the Philippines) are conspicuous examples. Another key trend is strategic alignment, deepening defense cooperation between the Japan-U.S. alliance and U.S. regional allies. 

Japan is at the center of this trend. Tokyo set the tone for regional security through the release of three strategic documents in December 2022: the National Security Strategy, National Defense Strategy and Defense Build-up Program. The National Defense Strategy recognized that Japan is facing “the most severe and complex security environment since the end of” World War II. To address this security environment, Japan is adopting three distinct but mutually reinforcing approaches with regional deterrence in mind. First, Japan is increasingly committed to its own defense by strengthening its defense capabilities, including acquiring long-range strike capabilities. Second, Japan works ever more closely with its ally, the United States. Third, Japan sets out to deepen its security ties with like-minded countries, mainly those supportive of Japan’s diplomatic vision of a Free and Open Indo-Pacific (FOIP). These can be seen as significant shifts in Japan’s defense policy accompanied by its historic defense spending boost. 

Australia is following a similar strategic direction. While adopting the strategy of denial as its foundation, Australia’s National Defense Strategy, released in April 2024, prioritizes regional security partnerships for deterrence. In October 2022, moreover, Japan and Australia officially affirmed their strategic partnership and signed the Joint Declaration on Security Partnership for enhancing strategic alignment and promoting peace and stability in the Indo-Pacific. 

As the examples of Japan and Australia show, the regional security challenge increasingly unites regional countries. They understand deterrence is essential and requires close defense cooperation to achieve. 

Deterrence is essentially a psychological function to influence an adversary through anticipation of the dire consequences of his own behavior. The goal is to convince an adversary that taking a hostile action will lead to a dreadful outcome, thus preventing the action from ever being committed. With this point in mind, effective collective deterrence must meet three conditions. First, it has to be realistic and viable to the adversary; an unrealistic or infeasible deterrent is easily discounted. Second, the adversary must be convinced that a hostile act would be met with a collective response, denying any meaningful gain or advantage. This gives an impression that the adversary will be challenged by multiple actors even when dealing with only one specific target.  Third, it has to show the adversary that the collective actors are willing to demonstrate their resolve by taking a hard choice – i.e. accepting risk – during peacetime.   

When it comes to collective deterrence, “forward presence” and “force multiplier” are key concepts to consider.

Forward Presence 

Forward presence is the periodic, rotational, or permanent deployment of armed forces in forward bases. It also comes in the forms of access and storage agreements, joint military exercises, port visits, and security assistance. 

Japan, with its proximity to China, stands on the frontline of Chinese military threats. China is expanding its missile capabilities, which increasingly make it challenging for other militaries to operate near China. This could make it risky to conduct military operations from Japan, and it is operationally prudent to disperse forces far from China. Yet exactly because Japan is in close proximity to China and under its missile threats, forward presence in Japan plays a key role to demonstrate the United States’ resolve in accepting risk. 

The U.S. Marine Corps’ operational concept of Expeditionary Advanced Base Operations (EABO) is particularly salient here. Under the concept, by deploying small and dispersed units focused on survivability and lethality, U.S. Marines set out to operate in forward locations (e.g. a contested area) to conduct sea denial and forward sustainment operations equipped with anti-ship missiles. Its stand-in posture demonstrates resolve and readiness to fight under severe fire. 

Also, due to the geographical proximity to China, a U.S. forward presence in Japan directly challenges China’s expansionist tendencies. In the severe security environment, physical presence is the visible display of firm commitments to regional security. It is also important to note that prepositioned capabilities enable the United States and its allies to respond swiftly to a crisis. In this respect, the maritime nature of the regional environment can have strategic benefits if a large number of drones and mobile missiles are prepositioned. In addition to Japanese land-based territory, the United States and its allies can theoretically deploy drones and launch mobile missiles in, under, and over the seas, multiplying the number of targets and amount of fire power that China would have to confront.

How about Australia? Australia has demonstrated its capacities through joint military exercises and training in the region since Australia and Japan signed the reciprocal access agreement  in January 2022, providing both countries’ military forces with access to the other country for joint military training and exercise. 

As an example of regional defense cooperation, just before the first historic summit among the United States, Japan and the Philippines at the White House in April 2024, the three countries, joined by Australia, conducted the first joint naval exercises in the South China Sea. This sent a message that whoever challenges the Philippines cannot expect to deal with that country alone. 

In the future similar types of bilateral, trilateral, and multilateral exercises should be expected near contested waters. If they are conducted on a more frequent and regular basis, these drills will create a situation where multinational forces constantly operate in the contested areas. Over all, a more visible presence of forces can raise the costs of aggression and generate uncertainty about the adversary’s success in achieving its objectives.

Force Multiplier

It is also worth considering the concept of “force multiplier.” One strong advantage of having allies is the aggregation of capabilities. If coordinated well, combining U.S. capabilities with those of regional allies can serve as a force multiplier that considerably improves the overall combat capability of allied military forces. This may require more prepositioned equipment and weapon stockpiles. Establishing joint ammunition depots and fuel stations in forward locations is one possibility. Another would be to improve interoperability by possessing and employing the same types of systems so that they can supplement each other when needed. 

Indeed, Australia and Japan have started to acquire operational capabilities (long-range missiles, submarines, and drones) intended to deny an adversary’s swift operational success. Such capabilities include the Tomahawk missiles Australia and Japan will purchase from the United States. In theory, they can be supplied to one another when needed. 

This move, however, goes beyond simply acquiring the same missile capability for mutual aid, and it entails closer coordination, joint targeting, and planning. The United States and Japan have already begun joint training for the operational employment of Tomahawk missiles. As announced in the joint statement of the U.S.-Japan Security Consultative Committee (or “2+2”) on July 28, 2024, the countries have set out to closely coordinate stand-off missile operations. In the future, it is not difficult to imagine that the United States, Japan and Australia will collaborate and work on joint planning for such operations. Combined Tomahawk missile capabilities will more effectively deny an adversary’s maritime targets. As U.S. and Australian leaders have noted, “Enhancing trilateral interoperability is an important investment in credible, effective deterrence.” 

Expanded defense industry collaboration among the U.S. allies can also serve as a force multiplier. The three countries now agree on the joint development of next-generation military drones. Successful drone development will give them a chance to acquire the same capability, providing a significant opportunity. As they employ the same drones, they should be interchangeable in the case of a contingency. To this end, ideally the drones will be produced in a ready state and prepositioned for maximum effective employment in a time sensitive manner. 

The U.S. and Japan have already agreed on this approach with respect to other systems. On July 28, the two governments at the 2+2 meeting agreed to expand Japan’s capacity to produce Advanced Medium-Range Air-to-Air Missile (AMRAAM) and Patriot PAC-3 missiles in Japan. The latter missiles are already produced in Japan under license, and the former missiles will be newly produced in Japan. The production capacity will thus be expanded in order to “address timely procurement and readiness requirements, and deter aggression.” 

Finally, the possession of the same asset can significantly improve joint firepower. The C-130, a versatile transport airplane, is one such asset. The U.S. Air Force is developing a missile system program  named Rapid Dragon that allows C-130s to drop long-range palletized munitions, similar to the way C-130s normally airdrops supplies. One huge advantage of Rapid Dragon is that dozens of countries, including Australia and Japan, operate C-130s and the missile system can be introduced without aircraft modification. The two countries could technically employ the same missile system, which adds more firepower in the Indo-Pacific. Should they be dispersed in forward locations, the aircraft’s ability to take off and land on short austere runways creates not only visible forward presence but also fear in the adversary’s mind that armed aggression will suffer severe damage and costs through collective efforts. 

These approaches will reinforce the three conditions for effective and viable collective deterrence. They are, nevertheless, just a starting point for exploring the subject further. While the United States, Japan, and Australia are three key actors to form collective deterrence, they are not the only ones invested in this task. More extended access to foreign bases and overflight is, for example, something worth pursuing down the road. 

More effective deterrence requires more collective, coordinated and consistent approaches among additional regional countries. They are now clearly aware that a devastating storm is quickly approaching. Although there is always a possibility that it may not hit home, it is sensible to assume that the storm will hit the region to raise the sense of urgency and prepare themselves. 

At the end of the day, credible deterrence, while expensive, is far cheaper than war.

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