From Land to Sea: Australia and South Korea in the Indo-Pacific

4 December 2024

Australia and South Korea have been strengthening their security cooperation. In December 2023, the Australian government signed a contract to purchase Hanwha’s Reback infantry armed vehicle worth seven billion Australian dollars. In May 2024, the Australia-Republic of Korea (ROK) 2+2 meeting reaffirmed their joint commitment to upholding the rules-based order in the Indo-Pacific region. Given that both are close US allies and share liberal democratic values, their collaboration is unsurprising.

Australia was the second country to deploy forces to assist South Korea during the Korean War, following the US, and it remains a part of the United Nations Command (UNC) on the Korean Peninsula. Although their cooperation has historically focused on the peninsula, it must now extend to the broader maritime realm of the Indo-Pacific. Free and open sea lines of communication, especially in the South China Sea — through which critical trade and energy supplies for both countries flow — are increasingly under threat due to China’s rise. These shared concerns incentivise both Canberra and Seoul to deepen their commitment to a maritime order that respects the freedom of navigation.

For South Korea, the persistent threat from North Korea remains a priority, making it reluctant to allocate resources to security concerns beyond the peninsula. Australia can bolster Seoul’s confidence by reaffirming its commitment to peninsular security.

The Korean War was a pivotal event in fostering security cooperation between Australia and South Korea. Canberra deployed 17,164 military personnel, 339 of whom perished in the war. Australia’s contributions spanned the army, navy, and air force, and its military remained in Korea as part of the British Commonwealth Forces Korea until 1957. Even after withdrawing its forces, the Australian Defence Force (ADF) maintained liaison officers within the UNC, recently taking on major leadership roles. Thus, bilateral cooperation has been driven by the threat of North Korea. However, the rise of China has introduced a new, mutual geopolitical challenge that demands a broader scope of collaboration.

Evolving maritime partnership

The maritime domain has become a focal point of security concern in the Indo-Pacific, particularly as China’s rise heightens the risk of conflict in the South China Sea and the Taiwan Strait. The People’s Republic of China (PRC) claims territorial rights over both areas, jeopardising regional stability. Both Australia and South Korea depend on secure sea lines of communication (SLOCs) through these waters for trade and energy supplies. Any disruption could severely impact their economies.

Both countries have acknowledged the importance of the Indo-Pacific region through strategic policies. Australia’s 2023 Defence Strategic Review states, “China’s assertion of sovereignty over the South China Sea threatens… Australia’s national interests”. Similarly, South Korea’s Indo-Pacific Strategy underscores the need to “deepen maritime security cooperation in the region… [and ensure] peace, stability, and freedom of navigation and overflight in the South China Sea”. These statements reflect the recognition in both capitals that maritime security is essential. However, despite recent interest, defence cooperation between the two countries has historically neglected the maritime realm, focusing instead on land-based threats from North Korea. Addressing maritime issues together, especially in response to China’s actions, represents a new and pressing challenge that requires fresh agenda-setting.

The future of maritime cooperation

Both Australia and South Korea have strategic reasons to collaborate on maritime security, given their reliance on stable SLOCs in the Indo-Pacific. Cooperation can help address each country’s vulnerabilities. For Australia, the sustainability of naval asset procurement is a key challenge. After the collapse of the Soviet Union, Australia’s shipbuilding industry declined due to decreased maritime threats, making the acquisition of new warships a persistent issue. South Korea, a leader in shipbuilding, can provide Australia with valuable support. For example, Hanwha Ocean — one of South Korea’s major warship manufacturers — has expressed interest in acquiring Australia’s Austal, a major shipbuilder although this deal was not successful.

Australia considered South Korean models for its new surface fleet acquisition plan, which includes “at least seven, and optimally 11” general-purpose frigates to replace the current Anzac-class frigates, which have a full displacement of around 3,600 tonnes. However, South Korean shipbuilders did not meet Australia’s requirements, including the desired capabilities of the frigates and other political considerations, leading to the exclusion of South Korean models. Nonetheless, this does not mark the end of potential cooperation between South Korea and Australia in shipbuilding. Australia continues to seek opportunities to enhance its indigenous shipbuilding capabilities, providing an avenue for Seoul to assist Canberra in capability development.

For South Korea, the persistent threat from North Korea remains a priority, making it reluctant to allocate resources to security concerns beyond the peninsula. Australia can bolster Seoul’s confidence by reaffirming its commitment to peninsular security. While UNC member states, including Australia, deployed forces during the Korean War, the UNC lacks binding authority to ensure redeployment in a contingency. Recognising this, the Yoon administration has emphasised the UNC’s importance, hosting its first ROK-UNC Member States Defence Ministerial Meeting in November 2023. Australia can further reassure South Korea by playing a larger role in the UNC. Recent efforts, such as appointing Vice Admiral Stuart Mayer as Deputy Commander of the UNC (2019-2021), demonstrate Australia’s commitment.

With strengthened mutual support, South Korea could allocate more resources to addressing maritime challenges beyond the Korean Peninsula. A cooperative approach to countering China’s maritime ambitions is essential for both nations, as neither can navigate this new geopolitical environment alone. Increased collaboration in the maritime domain will enable Australia and South Korea to jointly protect their interests and contribute to regional stability, especially in light of Donald Trump’s re-election in the US. The Trump administration’s “America First” policy may result in declining US commitment to significant regional matters, such as the South China Sea and the Taiwan Strait. As a result, both Seoul and Canberra have stronger incentives to enhance their cooperation, recognising the need to maintain the status quo with less support from the US.

DISCLAIMER: All views expressed are those of the writer and do not necessarily represent that of the 9DASHLINE.com platform.

Author biography

Dongkeun Lee is a PhD candidate at the Australian National University’s Strategic & Defence Studies Centre. His main research areas are maritime security and the role of the navies in the Indo-Pacific region. His recent publications include “Influences behind the development of South Korea’s shipbuilding industry from the 1960s to the 2000s” featured in Marine Policy. Image credit: Flickr/Office of the President-KoreaNet.