more so than the Australian government is letting on

The federal Labor government today used the ALP national conference to address internal dissent over the controversial AUKUS security pact and its plan for acquiring nuclear-powered submarines.

Taxpayers have been asked to fund these subs at an extreme cost, up to A$368 billion, and with many risks in the procurement cycle. This decision, and the price tag, can only be justified by the consideration that Australia would likely join the US in a war against China to protect Taiwan.

But the government hasn’t specifically acknowledged that. Its public rationale for going ahead with the subs is to counter China’s growing military influence in the Asia-Pacific, especially in the maritime domain.

“China’s military buildup is now the largest and most ambitious we have seen by any country since the end of the second world war,” according to Defence Minister Richard Marles.

But how great is China’s naval capability?

The truth is the US navy, alongside its allied navies, especially Japan, remains much more powerful compared with China’s navy – and that’s likely to continue.

The Australian government isn’t being fully open about the cost-benefit analysis. It hasn’t publicly laid out its case for why its pursuit of such extremely expensive subs in relatively small numbers would help redress negative implications of the Chinese military buildup for Australian security.

What’s more, the AUKUS arrangements add little to the security commitment the US and Australia already have. We already have the closest possible alliance with the US, and even the government has said to our Asian neighbours that AUKUS doesn’t upgrade the security guarantees of the US to Australia.

So how do we assess the naval balance of power between China and the US, and do the AUKUS submarines arriving in the 2030s figure in those assessments?

Comparing their navies: the old way

A traditional way of assessing the balance of naval power is to count and compare the number of warships operated by each country. Even on that metric, the US isn’t outgunned by China, based on recent data.

China is frequently described as the world’s largest navy. But the US has more of the most important types of major warships, which are suitable for maritime warfare. The count only shifts in China’s favour for lighter and less heavily armed ships, such as frigates and coastal patrol vessels.

China’s advantage in lighter classes of warships could be particularly important in a conflict contained largely within the Taiwan Strait and other coastal areas near China.

On the other hand, even though the US doesn’t normally deploy all its naval force to the Western Pacific, it could deliver overwhelming naval power in the region in most circumstances if war was imminent.

The ‘missile age’

In today’s world, the ability of a country to carry out missile strikes is a far more important consideration than simply the number of warships.

The US can readily compensate for China’s numerical advantage in light warship numbers with “stand-off” missiles, which can be launched from long distances (more than 1,500km).

Read more: The much-anticipated defence review is here. So what does it say, and what does it mean for Australia?

In modern war, the count of “weapons platforms” (any structure from which weapons can be deployed, including ships) is far less important than the number of missiles that can be fired from a variety of platforms against enemy targets.

A US think tank has estimated that in the event of China starting a war with Taiwan, the US could fire more than 5,000 anti-ship missiles over the first 3-4 weeks.

The simulation was pessimistic about whether this number would be adequate to hold the Chinese attack at bay or defeat it in the first weeks, but it still saw China suffer significant ship losses. The simulation didn’t include US attacks on Chinese naval bases, which could significantly alter the missile advantage in favour of the US.

In a war between the US and China, we could expect the US would be prepared to undertake crippling cruise missile strikes on naval bases and other targets inside China. Even on short warning, the US navy could, for example, launch more than 1,000 cruise missiles against the Chinese mainland in an initial engagement over several days if it chose to do so.

According to the US Congressional Research Service, the US navy has 9,000 missile vertical launch tubes to deliver long-range cruise missiles, compared with China’s 1,000.

The Australian public need not be so spooked about China’s naval buildup, given the US’s supremacy in the “missile age”.

The US also has the cyber advantage

The US navy also has superior cyber capabilities compared with the Chinese navy.

Its cyber resources are concentrated in its “Tenth Fleet”, with more than 19,000 active and reserve personnel. It has 26 active commands, 40 cyber mission force units, and 29 reserve commands around the world, which could be available to strike China in the event of war. Such missions would likely aim to disable, disrupt or destroy the command and control and fighting effectiveness of the Chinese navy.

For example, it was US navy cyber personnel, alongside Ukrainian counterparts, who successfully blocked what could have been crippling cyber attacks by Russia ahead of its invasion in early 2022.

In contrast, China doesn’t appear to have a dedicated naval cyber command, corresponding forces, or such a substantial global footprint.

Read more: Deterring China isn't all about submarines. Australia's 'cyber offence' might be its most potent weapon

The International Institute for Strategic Studies (IISS) has assessed that China is at least ten years behind the US in its cyber power.

This judgement is based on the US’s industrial and technological supremacy, and its much longer history of integrating cyber operations into military planning.

In a war with China, the US could count on the active support of key allies, such as the United Kingdom, Canada and Australia, through remote cyber military attacks against China.

The AUKUS pact enhances the strength of this cyber alliance. Australia having nuclear-powered submarines doesn’t hugely change the US/China balance of power.

The allied cyber capabilities together far outweigh those of China. China has no strong cyber allies and has weak cyber defences compared with the US.

What about the long term?

The Congressional Research Service’s May 2023 report assesses that the naval balance remains in favour of the US, especially in submarine capability.

It finds China would have to maintain its robust naval buildup and modernisation for quite some time if that were to change (though it doesn’t estimate a timeline for this). If that transpires, the report concludes China “might eventually draw even with or surpass the United States in overall naval capability”, though in my view this outcome is far from certain.

I estimate the US advantage in naval power over China will likely remain in place for at least the next decade, and probably longer. The government owes the Australian public a granular accounting of the military balance for the longer term.