How Australia and South Korea Are Recrafting Their Relationship and Fortifying the Indo-Pacific

Australia and South Korea share a comprehensive strategic partnership rooted in their defense of freedom and democracy in the Korean War. This shared security and economic interdependence between the region’s most prominent middle powers promote a free and open Indo-Pacific and form an important coalition of liberal democracies opposed to illiberal encroachment from China, North Korea and Russia.

AUKUS, the ongoing defense technology agreement between Australia, the United Kingdom, and the United States, presents engagement opportunities and clear incentives for South Korea. The main thrust of the deal is the delivery of conventionally armed nuclear-powered submarines to Australia’s navy. But Pillar 2 emphasizes “security and defense-related science, technology, industrial bases, and supply chains” in conjunction with like-minded partners.

South Korea brings advanced capabilities in semiconductor and quantum technology production, while Australia offers a collaborative space in autonomous systems. Marrying these complementary strengths can accelerate the modernization of allied military forces in the region, enhancing their strategic posture and pushing the boundaries of what it means to be a middle power. For Washington, it’s reassuring that two critical allies are both proactively expanding their defense capabilities, share similar threat perceptions, and are seeking to lock in and compound their alliance with the United States.

SHARP APPEAL

There is robust debate in Canberra about whether it is wise to bet so strongly on a country on the precipice of re-electing Donald Trump, whose disdain for U.S. security commitments abroad generates real uncertainty in Australia, South Korea, and elsewhere. But these concerns have so far been outweighed by the belief that China poses an immediate threat to national security. President Xi Jinping has presided over the largest military build-up since World War II, overtaking the U.S. Navy in total numbers and using these capabilities to bully, harass, and delegitimize smaller states across Southeast Asia and claim vast swathes of the South China Sea. There are increasingly loud signals that a Taiwan invasion is inevitable.

At the same time, Australia and South Korea are hesitant to delink significantly from Asia’s largest economy, which accounts for around a quarter of their overall trade respectively. The challenge for Canberra and Seoul is balancing commerce and exchange with China while proactively defending the values, rules, and norms that allow both small and large states in the region to thrive.

One minilateral mechanism that was supposed to help with this, the Quad, has accomplished relatively little. Although Australia, along with Japan, the United States, and India, re-initiated the Quad in 2017 as a traditional security coordinating body, the grouping today is almost entirely non-military. The refocus on norms proliferation and knowledge-sharing hasn’t convinced Indo-Pacific states that the grouping is particularly impactful, however. With India increasingly looking like the odd one out, the Quad’s bandwidth to influence real change in the region seems to be narrowing.

Paradoxically, the Quad’s lack of impact may make it more appealing to regional actors who are happy to sign on to statements without taking any action. Meanwhile, AUKUS’s sharper edges and explicit military and technology goals have generated a more positive reaction in the region, specifically from states involved in maritime disputes with China. This may be because while many in Southeast Asia prefer to hedge between China and the United States, the perceived benefits of AUKUS are tangible and immediate enough to draw out the self-interest of these states and risk backlash from Beijing.

WORTH THE RISK

Beijing is highly critical of AUKUS and derides it as a Cold War anachronism that worsens regional tensions. This has not deterred South Korea and others from seeking out ways to participate. South Korea sees particular value in AUKUS’s so-called Pillar 2 and its proposed framework to enhance cyber security. State-sponsored cybercriminals in the region regularly target Korean defense and nuclear technology, and North Korea’s hacking army targets the National Aeronautics and Space Administration and the U.S. Air Force. Stronger cyber cooperation through advanced technology-sharing agreements like Pillar 2 is crucial to identifying, defending, and deterring such cyber crime. It also provides opportunities to multilateralize domestic initiatives like the newly established Defense AI Center. This is part of an ongoing effort by the Yoon Suk Yeol administration to pull in resources from the public and private sectors and coordinate effective responses to emerging threats. Korea has the third-most AI patents in the world, while Australia attracts significant investment in the AI industry. Pillar 2 can serve as the mechanism to pool these resources and amplify mutual capabilities.

The immediate and narrow benefits AUKUS offers for participants have attracted buy-in from around the region. Indonesia, for example, came out strongly against the deal when it was first announced in September 2021 and suggested AUKUS challenged the non-proliferation regime. Three years later, however, president-elect Prabowo Subianto signed a landmark defense cooperation deal with Australia that will almost certainly include technology transfers under Pillar 2 to promote “joint activities and exercises” between the two countries’ militaries.

South Korea faces similar and potentially more severe security threats from China considering its close proximity and greater economic exposure (South Korea’s trade as a percentage of gross domestic product is nearly double Australia’s). Seoul backed Canberra’s July 2024 condemnation of Chinese state-sponsored cyber crime targeting Australian government and business networks. With Australia and South Korea already advancing their technological defense capabilities, cooperation between their cyber and technology innovation sectors envisioned by AUKUS Pillar 2 can amplify both countries’ abilities to defend against new and emerging threats in cyberspace.

Spurred by these security challenges and seeking ways to diversify trade away from China, South Korea is quickly becoming a top arms exporter, shipping out some US$14 billion in missiles, rocket systems, Howitzers, tanks, and other material to a dozen countries last year. The Yoon administration envisions South Korea as a top four weapons supplier by 2027, and South Korean defense firms are expanding their footprint in Australia. Hanwha — the South Korean conglomerate that won a US$1.6 billion contract this year to deliver dozens of Chunmoo multiple launch rocket systems to Poland as part of a record defense contract signed months after Russia invaded Ukraine — is scheduled to build 129 next-generation “Redback” infantry fighting vehicles for the Australian army at a state-of-the-art factory an hour west of Melbourne. When the factory opened this year, Australian Deputy Prime Minister and Minister for Defense Richard Marles called it a testament to Australia’s and South Korea’s “strategic” relationship “cemented through defense” cooperation.

Against this backdrop, expanding AUKUS to include South Korea would be a practical step to promote its diversity, representation, and legitimacy. Forging greater ties with a like-minded democracy in the region has relatively low political costs for Australia and helps assuage the concerns mentioned above about whether Australia is too dependent on a potentially unreliable security sponsor in the White House. South Korea and Australia took a step toward such collaboration at their most recent 2+2 talks in May 2024, which Australian Foreign Minister Penny Wong described as a “cornerstone” of the South Korean–Australian partnership. The talks focused on deepening security and economic cooperation to reinforce shared visions of the Indo-Pacific and broader rules-based international order. There is mutual recognition in Seoul and Australia that they are represent pivotal, like-minded partners with which to promote democratic liberal values, stand up against Chinese aggression, and deter a possible war against Taiwan.

THE NORTH KOREA ANGLE

AUKUS and defense contracts are two significant platforms on which Australia and South Korea are reinforcing their relationship to address security challenges in the Indo-Pacific. For South Korea in particular, aligning with a similarly positioned democratic middle power in Asia that shares many of its priorities is one way to broaden its gaze beyond the important but long-calcified North Korea issue.

A 2023 government assessment of South Korea’s Indo-Pacific strategy supports this shift to protect Seoul’s “vital interest in the stability and prosperity” of the region. This aligns South Korea’s strategic security goals more closely with Australia’s, as outlined in the latter’s 2024 National Defense Strategy, which emphasizes the importance of collective security to insulate from regional instability caused by a revisionist China and its competition for pre-eminence with the United States.

Whenever North Korea forces South Korea to pay attention again, either due to a major provocation such as a nuclear test or border attack or an opportunity at détente like Pyongyang’s sudden about-face in early 2018, the Kim Jong Un regime will be negotiating (or menacing) with close backing from Russia. In addition to enhanced alliance and nuclear planning mechanisms with the United States, South Korea can further mitigate the new Russian–North Korean axis by sustaining its partnership with Australia.

Although inter-Korean relations may seem less serious from Canberra’s perspective, Australia is committed to enforcing the international sanctions regime against the North and would necessarily contribute personnel and material under its United Nations Command obligations in the event of a contingency.

ROUGH SEAS AHEAD?

Despite the significant appeal of Pillar 2, AUKUS still faces challenges. Many voters in Australia remain skeptical of the deal, either because of its long timeline, costs involved, or the perception that it makes a contingency with China more likely than not. Although some states are on board, Canberra will have to continue expending significant diplomatic capital, particularly across the Association of Southeast Asian Nations, to convince the region that AUKUS is in their interests. The United States and United Kingdom do not have the same burden because they are located much farther away from the region.

Expanding ties between Australia and South Korea is an opportunity to bring skeptics on board with the AUKUS deal. Both countries share common liberal values, are similarly anxious about an assertive China, and want the United States to expand its security presence in Asia to defend the former and deter the latter. AUKUS, U.N. Command, and weapons trade provide platforms for middle power cooperation and alignment between South Korea and Australia while defanging accusations that these platforms are exclusionary.

Arius M. Derr is a Research Officer at the Strategic and Defence Studies Centre (SDSC) and a doctoral researcher at The Australian National University. His work focuses on U.S. nuclear policy and U.S.-DPRK relations.

Hannah Cho studies economics, commerce and international relations at The Australian National University.

Image: The Australian Government via Wikimedia Commons

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