More than 30,000 personnel from 19 countries are honing their skills in the biennial military exercise Talisman Sabre, including live-fire drills and air combat operations.
But the exercises are being held against the backdrop of the US pressing allies such as Australia to make clear what role they would play in a real conflict, like a potential war between America and China over Taiwan.
The US is also carrying out a review of the AUKUS security pact, which would supply Australia with nuclear submarines from America.
Defence analysts say it's unlikely the review would result in the $368 billion submarine program being scrapped altogether, it may mean more demands of Australia to contribute to America's industrial base.
The military drills off the coast are also expected to be monitored by China, as it has for the past four Talisman Sabre exercises.
Prime Minister Anthony Albanese, who is visiting China for the second time as leader, is expected to raise security issues when he meets with President Xi Jinping on Tuesday.
Asked if Chinese spying was the act of a friend, the prime minister told reporters in Shanghai on Monday he will "continue to assert Australia's national interest".
Mr Albanese previously said he wanted the status quo to remain in place for Taiwan, when pushed if Australia would back the US in a war against China.
Opposition Leader Sussan Ley said the coalition also didn't want unilateral change.
"One of the reasons why we have committed, in terms of policy, to spending three per cent of GDP on our defence, that's important for the peaceful preservation of the status quo and for our region more broadly," she told reporters in Perth.
Meanwhile, two-thirds of respondents in an Australia Institute poll want a separate parliamentary inquiry into AUKUS.
The survey found 66 per cent supported a review of the security pact, representing a jump from previous polls.
Fewer than half of the more than 1500 respondents believed the AUKUS deal would make Australia safer.
A healthy democracy should welcome scrutiny of the agreement given its size and scope, the Australia Institute's Emma Shortis said.
"It is truly extraordinary that of the three countries that are party to the deal, Australia, which bears the brunt of both the cost and the risk, is the only one not to have put AUKUS to a genuine review," she said.
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