But that's unfortunate. The cost alone (which has already grown since you began reading this column) demands our attention, as do all the other "challenges" plaguing the project. The conference itself would never have possibly been able to solve the problem it set itself - how to procure a submarine with all the capabilities of a nuclear-powered one without installing a mini nuclear reactor. That's for one simple reason: it can't be done.

Both the Coalition government and the Labor opposition have repeatedly announced they're not prepared to wear the political opprobrium of even considering nuclear-powered, let alone nuclear-armed, boats. No matter how militarily sensible either of these possibilities might be, they are both, currently, politically impossible. It's that qualification, however - currently - that's fuelling the enthusiasm of those determined submariners still trying to alter the scope of the project to include some nuclear capacity - and, again, there's a reason for that.

It's because they know the current project doesn't make any sense without

The only way of unravelling this problem is to go back to the beginning and review the original problem set for France's Naval Group, the designers of the new vessel.

The then-PM, Malcolm Turnbull, had a simple political problem. He wanted - needed - to find an urgent way to cauterise what had become an ongoing political sore since Tony Abbott had cut through the bureaucratic tape to choose a cheaper Japanese design for the subs. He asked the French if, for a hundred or so million, they'd simply be prepared to begin design work. Naval said, "bien sur, but of course", and the political heat suddenly vanished. The problem itself, however, hadn't disappeared; it had just been pushed aside for a couple of years.

That's because the ask was impossible. Turnbull wanted a submarine that could remain underwater indefinitely, like a nuclear one, but one that wasn't nuclear-powered. The navy wanted it to carry new, highly capable weaponry, even though it didn't know what that was because it hadn't yet been designed. The specifications demanded the boat would be small and stealthy, yet large enough to carry a range of equipment packages to carry out multiple missions. It needed to sail deep, so as to avoid detection and be invisible to sensors, but also speed through the water silently. There were other requirements as well, of course, such as "future proofing" the new class so it would be able to remain effective well into the 2050s and beyond, even though we could never have any idea of how vastly scientific advances will transform the underwater operating environment.

Achieving just one of these attributes would represent a remarkable feat of engineering. Managing all of them, in combination, to obtain an effective attack-class submarine? Utterly impossible.

No matter how enthusiastically we attempt to unpick this puzzle (and I'm all for taking on ambitious projects) the essential problem remains: it can't be done. Take propulsion - the engine that powers the boat to move through the water.

The current agreement is that the subs will be battery-powered. These run quiet underwater, and their capacity is increasing all the time. The problem is they still need to be charged, which means "snorting" near the surface: a critical limitation, because it risks exposing the vessel to detection. The other issue is that batteries can't - at the moment - provide the sudden surge capacity that other fuels can, meaning the boats require two power-trains. But this adds more weight and space to the envelope, and larger submarines can't dive as deep unless the hull is reinforced. This adds to the profile, which requires a bigger engine, which makes the boat easier to detect, etc, etc.

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The big advantage of focusing in on any one major problem is that it sets into sharp relief the multiplicity of other equally critical issues surrounding this huge project.

The basic problem when it comes to submarine design is that trade-offs will always be required, and the wicked problems compound exponentially. Choices must be made between the major attributes of the platform, and each one will inevitably affect the shape of the total envelope. This is where the whole project comes unstuck.

Propulsion; arming; sustaining; upgrading; crewing; communicating - it might be possible to find a method of resolving the problems related to each and every single attribute. In combination, it's not.

The submariners don't accept this. Their strategy is one of "if only". Find a magic answer to one of the issues, such as going nuclear, and all the others will fall into place. It's based on the idea that there is a magic bullet for the submarine project, and today, nuclear power supposedly offers such a way. Tomorrow it will be something else, yet the insurmountable problem for its proponents remains. Both the Liberal and Labor parties refuse to contemplate establishing a nuclear industry, or even buying nuclear power plants offshore.

Until a way can be found to defeat the laws of nature, proponents of the submarine will continue to focus on this issue. The next idea to be floated will be the suggestion that perhaps the vessels can operate as control stations for fleets of remote autonomous weapons; or maybe used as launchpads for long-range missile systems. There's always some new panacea to distract and keep hope alive.

Just imagine what that money might be able to do if it was spent on developing a system that could work.

Envisage a future where instead of fighting against physics, we attempted to harness the properties of science to work for us. Is that really too much to ask for?