Briefed on AUKUS just a day before it was publicly announced, Anthony Albanese and his then-shadow cabinet quickly threw their support behind the partnership with the United States and the United Kingdom to furnish Australia with nuclear-powered submarines and other military technologies.

With a federal election looming that the Coalition was primed to fight on national security, casting doubt on a massive defence deal with Washington and London was a political nonstarter for Labor.

Despite the compelling political logic of Labor's AUKUS support, the national interest case has always been more contested. This was abundantly clear in the lead up to Labor's recent national conference, where we witnessed a public and vocal rise in AUKUS dissent among the party faithful.

But the Albanese government's persuasion problems on AUKUS go deeper than internal Labor party argy-bargy.

For all the AUKUS advocacy and the pomp and circumstance of presidential press conferences, the Albanese government has never given the Australian people a frank and forthright explanation of the military applications of nuclear-powered submarines.

The Albanese government has said that "we face a regional arms race" and that AUKUS is part of Australia's contribution to "collective deterrence of aggression". The enhanced "speed, stealth, and endurance" of nuclear-powered submarines will apparently help secure Australia by "being able to hold potential adversaries' forces and infrastructure at risk from a greater distance".

All that might be true in general.

But the Prime Minister and his ministers can and should say much more about how specifically AUKUS submarines will be used and how that will help secure Australia and the region.

Not least because, by the Albanese government's own admission, AUKUS is historically unprecedented for Australia-both in terms of the fiscal outlays and the capability's potency.

With a cost-of-living crisis biting and the federal budget under strain, the price tag of up to $368 billion demands much more public transparency. All the more so because the history of Australian defence procurements suggests that the final cost could be even higher.

But the military implications of AUKUS are more consequential still. The Australian Defence Force will have a more powerful naval capability than it has ever previously possessed.

Nuclear-powered submarines will give future Australian governments the ability to stealthily project military power to never-before-seen distances and strike adversaries without warning as far afield as China's eastern seaboard.

To be sure, the sensitive nature of undersea military missions means that not all the uses of nuclear-powered submarines can be publicly explained.

Still, the Albanese government's ongoing reticence leaves the Australian people unable to assess the potential risks and rewards of AUKUS.

Has Canberra chosen nuclear-powered submarines to allow us to make a much more meaningful contribution to any US-led effort to repel a Chinese invasion of Taiwan or deter Beijing from embarking on such a foolhardy campaign in the first place?

Will this long-range and high-endurance platform be used to put China's seaborne second-strike nuclear capability at greater risk? With their ability to stay on station in the deep waters of the South China Sea's northern reaches for extended periods, AUKUS submarines could be used to track and possibly attack Chinese nuclear ballistic missile-armed submarines leaving Hainan Island.

Or are Australian nuclear-powered submarines intended to add to the collective weight of the US-led military counterbalance to the People's Liberation Army in North Asia? Just as these possible uses of nuclear-powered submarines might be reasonable responses to a more dangerous world, these and other applications take us into the realm of daunting and potentially deadly hypotheticals.

The future risks of delivering a deterrent effect against China in its immediate neighbourhood or being more deeply enmeshed militarily with the United States do not necessarily undermine the case for nuclear-powered submarines.

But these risks show that the stakes for Australia are simply too high for ministers to justify AUKUS with imprecise claims about changing "the calculus of any potential aggressor".

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The lack of a frank and forthright explanation of the military applications of nuclear-powered submarines is also a likely liability for AUKUS' long-term success.

The Albanese government is asking the Australian people to embark on an expensive and high-risk endeavour that will reshape the hard power dimension of Australia's statecraft.

To realise that national project, our children and our children's children will need to accept the security rationale for AUKUS and believe that it warrants vast public expense. Lowy Institute polling shows that public support for AUKUS has already softened. Sustaining such support over generations will be even harder as China ramps up its disinformation efforts aimed at muddying the distinction between nuclear-powered and -armed submarines.

More clarity and candour will be needed from Canberra to keep Australians on board.

Threading the needle of having a more open national conversation about AUKUS while not aggravating Beijing or causing diplomatic disquiet in Washington will be hard. But for a democracy like ours, anything less than a transparent explanation of the military case for AUKUS just isn't good enough.