Kevin Rudd insisted he wanted submarines: not just six replacements for the Collins, but so much more. Why not 12 of the very best in the world? Labor voters were happy about the jobs; Coalition supporters saw he was serious about defence; and, perhaps best of all, nobody would have to pay anything for years ...

Well, the bill's finally arrived - and the government isn't happy.

Submarines aren't cheap - particularly if you want them to survive. To do their job they need to be invisible, and unfortunately that's diametrically opposed to the entire trend of scientific discovery, which is revealing more and more about the world around us. It's becoming easier and easier to detect objects underwater, meaning boats need to be stealthier and deadlier. Can it be done? Possibly not. It's certainly going to be tricky, and detailed research, good research, is going to cost. A lot.

Attempting to spout exact "acquisition costs", like $30 billion (the starting price), $50 billion (2016), $80 billion (Rear Admiral Greg Sammut to Parliament in November) or $145 billion (their whole-of-life running cost, an additional figure) is a bit silly, because they're just guesses. What make more sense are comparisons. The sixth Japanese Soryu-class submarine costs just a fraction over $803 million, while the better SAAB A26 has an estimated unit price of $1.46 billion - both considerably cheaper, and possibly just as capable, as the proposed Attack-class subs.

There's no doubt the federal government is paying a huge premium, but then again, isn't what you'd expect if you order the best (conventional) submarines in the world? That's what France's Naval Group is attempting to deliver, but the excellence in design doesn't come cheap. This is the bill for what's been ordered. Anyone quibbling over cost simply hasn't being paying attention. Malcolm Turnbull accepted the premium when he chose a French designer and, just like haute couture, you only get what you pay for.

Perhaps the real question is, why has this issue suddenly hit the headlines now?

Three possibilities. The first is that recent reports of Defence officials thinking about scrapping the Naval Group contract are simply a confection, designed to put pressure on the French company as the Aussies negotiate the next phase of the project. The problem is that as soon as Turnbull chose the French he dismissed the competition, with the inevitable result that there was no pressure to keep the price down. Perhaps someone on the submarine project realised this was a mistake. Perhaps they fed this story to a reputable journalist (The Fin's Andrew Tillett broke the news) as a way of creating a bogyman. Perhaps it's just an effort to keep the French honest - nothing more, or less, than that. Rear Admiral Greg Sammut, the man in charge of the project, won't speak to me about this issue.

Second is that it's a genuine attempt to push the government into examining other options. Many experts including Derek Woolner, the bloke who literally wrote the book on the tribulations of the Collins class, point out the current upgrade of the existing fleet never figured in the original evaluation. Political bastardry deliberately excluded the brilliant, new Swedish A26 design from the original competition, even though this had directly evolved from the Collins.

The A26 is a cheaper design powered by cutting-edge lithium ion batteries from, ironically enough, Adelaide-based PMB Defence. Finally, after years of problems (and just at the moment Australia's proving it can actually be a leading producer of defence equipment) the government chose to offshore the project. It scrapped all the investment it had pushed into the Australian Submarine Corporation, writing it down to nothing and excluding ASC from a role with the new submarines.

Where's the logic there?

Defence Industry Minister Melissa Price doesn't have a seat around the cabinet table, but perhaps (like her predecessor Christopher Pyne) she should. Price is a strong advocate for Aussie industry, and understands the complex interplay between production, technology and capability in military equipment. Maybe what the government actually needs to do is look at the whole issue afresh, because this project continues to be (as ANU lecturer Andrew Davies pointed out years ago) a very, very hungry caterpillar.

MORE STUART ON ATTACK-CLASS SUBS:

The third possibility is that the yarn originated with people who think (perhaps "realise" is a better word) this is the last chance to derail the whole, complex and massively expensive project before it disappears down the fundament of scientific impossibility.

Even if everything went perfectly - and it won't - the boats are being designed today to operate in a world 30 years hence. An example of the pace of progress comes from the realisation that when the Collins-class subs were being designed, the newest personal computer was the expensive 286K. Today that technology is left way behind by any smartphone. The world changes faster than submarines can be built, and they'll be obsolescent by the time they submerge.

The other issue is that even 12 subs won't cut it any more, because the waters of the Pacific are becoming crowded with these vessels. Perhaps a better solution might be to experiment with uncrewed, remotely controlled submersibles. Dramatic advances in artificial intelligence mean these can now achieve tasks that formerly required submarines. In fact, it's difficult to see any advantage at all being conferred by crews that need food to eat, bunks to sleep in, oxygen to breathe and can't go as deep (or present the tiny profile) of autonomous systems.

So what's likely to happen?

Why, we'll go ahead and re-sign with Naval, of course! When has the government or Defence ever pulled out of a project just because all the warning signs were there, bells ringing, lights flashing, and a loud voice screaming, "Warning! Warning!" Reef ahead? Oh, don't worry about that. This time it will all be different.