The unusual deployment by three navy ships over the past month has prompted a debate in Australia about its aging fleet and reliance on the United States.

Both Australia and New Zealand have another worry, that China may be strengthening its ability to deploy its forces in the region by cosying up to South Pacific microstates. In February the Cook Islands agreed to form a “comprehensive strategic partnership” with China and announced plans for Chinese investment, including port-building.

For nearly a month, three Chinese warships made an unannounced journey around Australia, leaving the country on high alert. The flotilla consisted of a cruiser, a frigate, and a replenishment tanker,