India, which is planning to hold its annual naval exercise with the United States and Japan in the Bay of Bengal next month, has announced that Australia is also to participate.

The Malabar exercise started in 1992 as bilateral drills between the Indian and the US navies, before Japan joined them in 2015. Australia participated in the 2007 exercise along with Singapore.

But with India describing Australia's acceptance of its invitation to take part this year as a sign of cooperation between the members of the so-called Quad, it has naturally raised speculation that the four countries are planning to strengthen their military cooperation under the framework of a common Indo-Pacific strategy aimed at containing China.

With the US under the Donald Trump administration adopting an increasingly antagonistic stance toward China, it has given fresh impetus to the informal quadrilateral security dialogue as the administration has been pushing for greater collaboration with Japan, India and Australia to buttress its bid to contain China's growing regional influence.

Yet it is still premature to say that the other three Quad members are now dancing to the US' tune, especially as the US has not tied its interests with those of the other three countries.

For Japan, India and Australia, China is a close neighbor and an important trading partner. Despite their differences with China, these three countries know that, rather than treating it as an enemy, expanding cooperation with China will best serve their interests.

Although Japan still views its alliance with the US as the bedrock of its defense policy, it will not wish to draw itself so close to the US that it weakens its strategic autonomy.

India, too, will be unwilling to relinquish its strategic autonomy to play a subordinate role to the US even though it looks to the US for support having reignited its border dispute with China.

And in Australia's case, even though its ties with China are at their lowest point in years, it has no fundamental differences with China and it is hard to see the benefits it would accrue from seeking a more active role in the anti-China campaign of the US.

China has been critical of the Quad, saying that instead of forming a clique to pursue their selfish interests, they should think more of the regional countries' common interests and engage in multilateral cooperation that is open, inclusive and transparent.

The regional partners of the US will calculate the pros and cons of whether to voluntarily serve as chess pieces of the US in its confrontation with China. In doing so, they should bear the bigger picture in mind.

From a geopolitical perspective, if the three countries bolster the US' ambition to heighten its strategic confrontation with China in the region, no party will emerge a winner.