Tokyo and Canberra are taking steps to reinforce their security arrangements, with both governments concerned about an unstable and nuclear-armed North Korea and an assertive China. Julian Ryall reports.
Australian Prime Minister Malcolm Turnbull embarked on a one-day trip to Japan on Thursday and held talks with Japanese PM Shinzo Abe and other high-ranking officials about security in the region.
Significantly, the first destination on his whistle-stop tour was to a Japanese military base. Turnbull and Abe flew to the Japanese Ground Self Defense Force Narashino training area, where they inspected a US Patriot anti-missile system and Australian-made Bushmaster armoured transport vehicles used by Japan.
Both leaders also watched a series of exercises by a specialist anti-terrorist unit.
Defense and security are high on the agenda of both leaders, with both Abe and Turnbull expressing concern about a nuclear-armed and deeply unpredictable regime in North Korea and an assertive government in China.
"Abe is particularly keen to build on the 'quad' security partnership that brings Japan together with the US, India and Australia in the Asia-Pacific region and he is taking every opportunity to underline Tokyo's commitment to the solidarity of that mechanism," said Jun Okumura, a political analyst at the Meiji Institute for Global Affairs.
The loose four-way alliance is being pushed hard by Japan, which has become increasingly alarmed at what it considers as Beijing ignoring international laws and norms, as demonstrated by its absorption of a series of uninhabited atolls and reefs in the South China Sea.
China initially claimed that the islands of the Spratly and Paracel chains - which are claimed wholly or in part by the Philippines, Vietnam, Taiwan and Malaysia - were merely being equipped with navigation and harbor facilities to assist fishing fleets. But it has since transpired that the islands have garrisons of Chinese troops, runways capable of handling fighter jets and anti-aircraft missile batteries.
Tokyo is locked in a long-running dispute with Beijing over the sovereignty of another group of islands, the Senkakus/Diaoyus, which are controlled by Japan but are uninhabited and undefended, meaning it would be a relatively straightforward operation for Chinese forces to occupy them.
Equally, China is busy developing a blue-water navy that includes aircraft carriers and nuclear-powered submarines.
"I do not believe that Australia sees itself as directly threatened by North Korea's missiles, but it is clear that they are concerned by the inroads that Beijing is making into parts of the Pacific that Canberra has traditionally considered to be its sphere of influence," Okumura told DW.
Read more: South China Sea - what you need to know
Earlier this month, China responded angrily to claims by Concetta Fierravanti-Wells, Australia's minister for international development, that China is pouring aid into Pacific island states but creating "useless buildings."
In a press conference in Beijing on January 11, Foreign Ministry spokesman Lu Kang said, "We hope that certain people in Australia engage in self-reflection instead of pointing fingers at and making irresponsible remarks on other countries."
Beijing has reportedly provided $1.8 billion (€1.47 billion) in aid to Pacific island states, including almost $650 million to Papua New Guinea alone, in the last decade. Other recipients of Chinese assistance have been Fiji, Samoa and Tonga, with some suggesting that Beijing is seeking to buy influence in those countries and ease them away from the support that has traditionally been provided by Australia, the US and other international organizations.
"Australia feels that China is attempting to exert undue influence in their 'neighborhood' and that they have gone too far, but that attitude means that there is a real possibility of at least some form of low-level conflict between China and Australia," Okumura added.
In January 2017, Canberra and Tokyo concluded an updated acquisition and cross-servicing agreement, which permits both countries to provide ammunition, food, water and other supplies to the other.
Abe and Turnbull are now looking to build on that defense agreement.
An enhanced pact will stipulate the legal status of military personnel temporarily stationed in the partner country for joint exercises. The agreement will enable the two countries to transport military equipment and ammunition onto each other's territory in the event of a crisis, such as hostilities breaking out on the Korean Peninsula, and facilitate joint military exercises.
Further security dialogue
"Both governments are eager to engage in further rounds of security dialogue and Australia is growing increasingly concerned about China's activities in the South China Sea and the fact that it has declined to obey international law," said Stephen Nagy, a senior associate professor of international relations at Tokyo's International Christian University.
"The agreement that they are talking about is more of a tactical alliance than a full and formal alliance, but it is a step forward in enhancing the strategic partnership as they pursue joint training, interoperability of military systems and so on," said Nagy, who is also a fellow of the Asia Pacific Foundation of Canada.
Australia is wary of causing too many waves with China due to the importance of bilateral trade and the close economic partnership that has developed in recent years, Nagy added, but the government has clearly decided that it needs to take steps to help prevent the existing stresses and strategic uncertainties from worsening.
Turnbull and Abe also want to strengthen their nations' trade relationship, with both Canberra and Tokyo reiterating their commitment to pushing ahead with nine other nations to enact the Trans-Pacific Partnership free trade deal, despite the withdrawal of the United States from the framework last year.