Well, I just hope our shiny new subs don't swell up on contact...

Well, I just hope our shiny new subs don't swell up on contact with salt water like the current fleet...... ☺

Best use for the Collins Class subs, in the event of friction with our northern neighbours, would be to drop them on the Indonesians - they won't be expecting THAT.

Realistically, conventional weapons and approaches are a waste of time for a country in our position. The big boys would wipe the whole lot out in a blink if things got nasty. We need to play the game smarter - JORN over-the-horizon radar being one example. Small, fast, low radar signature catamarans for example - we're good at those. A fleet of 4 conventional subs would be more than adequate (with a view to keeping at least two of them at sea...) - why waste money on more than that?