In September 2021, the United States and the United Kingdom announced a plan to share submarine technology with Australia in a security pact awkwardly dubbed AUKUS. This was a particularly big deal at the time since the United States shares this technology with only one other ally, the United Kingdom. However, there is some debate over AUKUS’s utility.

In early December, Michael O’Hanlon, the Director of Research in Foreign Policy at the Brookings Institution, drafted an op-ed asking a foundational question about the trilateral security pact: is AUKUS floundering? AUKUS, he notes, has become a central piece of the Biden administration’s grand strategy of shoring up alliances in the Asia-Pacific region – alongside building up the Quad and working to improve the testy relations between two key U.S. allies, Japan and South Korea. However, AUKUS appears to be in trouble, as he anticipates that  the alliance could “wither on the vine.” If AUKUS is, in fact, withering, expansion could help strengthen the pact. If this is the case, is expansion a viable option and which countries would be next in line to join?

Hurt Feelings

The AUKUS announcement infuriated a key U.S. ally: France. Not only were the French kept in the dark about the impending alliance, but it lost out on a lucrative submarine deal with Australia when Australia backed out of a contract with France to provide diesel-powered submarines in favor of the nuclear submarines promised by their American and British counterparts. In France’s mind, the announcement was a betrayal and resulted in France withdrawing its ambassadors from Washington and Canberra.  

However, there has been some speculation that France might be a potential candidate to join the non-nuclear portion of the alliance. In some ways, this makes a lot of sense. France seeks to position itself as a power in the Indo-Pacific, and already has a significant presence in the region. France is also the driving force behind the European Union’s strategic shift to the Indo-Pacific region. If the AUKUS partners were open to including France in the alliance – even the non-nuclear portion – it might go a long way in making up the monetary loss and diplomatic affront France endured at the initial announcement.

Left Out in the Cold

Two countries were overtly and, upon initial review, confusingly left out of the deal. Canada and New Zealand, members of the Five Eyes intelligence-sharing alliance alongside the United States, United Kingdom, and Australia, were not included. The leaders of both countries were visibly annoyed, at first, but quickly played down any speculation of a slight. After the initial news wore off, it became evident why neither country were founding members of AUKUS.

Canadian Prime Minister Justin Trudeau initially explained why the country was not included in the first place: Canada has not expressed any interest in building or operating nuclear-powered submarines. Similarly, New Zealand’s left-leaning Prime Minister, Jacinda Arden, reacted in a frustrated manner, stating that any nuclear-powered Australian submarines would not be allowed to dock in New Zealand waters. That frustration faded quickly, as New Zealand’s own policies against nuclear technology would make it difficult for inclusion in the program. It is unlikely that Canada or New Zealand, seemingly two obvious choices for potential inclusion, will join AUKUS at any point.

An Alliance Focused on the Asia-Pacific Region

One such reason for AUKUS’ purported trouble is that it encompasses only one country in the Asia-Pacific. For this reason, Japan has received the most attention in this regard. As Michael Auslin, a fellow at the Hoover Institution, points out, adding Japan to AUKUS could “transform security cooperation among liberal democracies in the Indo-Pacific like no other previous alliance or quasi-alliance has managed.” Japan’s security interests are already closely aligned with those of Australia, the United Kingdom, and the United States, particularly in light of concerns over China, North Korea, and Russia’s war in Ukraine.

Japan, a key U.S. ally in Asia for nearly 70 years, immediately joined U.S. and European efforts to sanction Russia after its invasion of Ukraine. Additionally, Japan attended the NATO summit in Madrid in June this past summer, signed a Joint Declaration of Security Cooperation with Australia in October, signed a reciprocal access agreement with the United Kingdom in December, and is cooperating with the United Kingdom and Italy to develop a next-generation fighter jet. Japan even announced in August that it would begin research on hypersonic missiles, shortly after AUKUS stated it would focus on developing such missiles. Japan is the next logical country to join AUKUS.

Debate over two other Indo-Pacific powers joining AUKUS has been held. South Korea seems to be another obvious contender. Also a major U.S. ally, South Korea is another like-minded, liberal democracy in the region with concerns over China’s growing aggression. South Korea, upon AUKUS’ initial announcement, noted the pact would likely contribute “to regional stability” and supported Australia’s decision to acquire submarines. Seoul has long sought to develop nuclear-powered submarines, but has been limited in the development of that technology due to a nuclear cooperation agreement with the United States. While South Korea’s inclusion may be a bit trickier, it is still worth considering.

Then, there is India. India, an increasingly important player in the Indo-Pacific region, never officially embraced or condemned the AUKUS deal. The country, however, has approached AUKUS with some trepidation, maintaining its distance while working to delink the Quad from the trilateral security pact. AUKUS’s tacit focus on China would play into India’s favor; however, India’s reluctance to engage in or even entertain alliances means that India will likely not be looking to join AUKUS any time soon.