Australia is expanding its military co-operation with the United States as China’s growing military strength and influence in the Pacific raise concern. The move highlights a strategic bind: Australia relies on the US for security while China is its biggest trading partner.

The joint Southern Jackaroo exercise with US and Japanese forces rehearses for a major conflict, though Australian officials have avoided naming a potential adversary. US Marines deployed to Australia have increased from about 200 in 2012 to around 2,500 today; US-linked facilities have also been upgraded, and the Aukus pact provides for Australia to acquire nuclear-powered submarines. A Lowy Institute poll cited in the article found that 31% of Australians trust the US to act responsibly in the world, while 28% trust China.