Its a very big hole of cost to Australia which is essentially a giant aircraft carrier for subs, a refuelling depot closer to the hot zone for asia-pacific war risk.

To stimulate future access, Oz is paying up front to maintain facilities in the US and UK, so that when eventually a modern sub design emerges, the production facilites exist and can supply the hypothetical subs to Australia, who meantime has hosted the existing Trident/Virginia boats, has had navy crew put through the nuclear vessel academy, has co-crewed subs, and at that point either owns 2nd hand stocks, has them leased, or gets to buy the new ones.

The main points of contention are independent thumbs on the trigger. That, and the 4 year election cycle risks in the US.

We had a perfectly cromulent FRENCH non-nuclear sub proposal signed up, which the French had made by DE_NUCLEARIZING their big nuclear sub for us. When we reneged, Macron went off because he felt lied to. Had he been told a nuclear bipartite deal was worth exploring, the French would have welcomed it.

The deal means that a) the US and the UK get to do france down b) the US gets money to keep shipyards operational c) RR and other SMR companies can go on to design and deliver a more modern one-and-done sub reactor (the French one required re-fuelling. the intention is the AUKUS one will be single fill lifetime operation) and d) Australia gets to shelter under a leaky umbrella when the obvious bad guy nation(s) in region muscle up.

Australia also gets to acquire nuclear engineering skills which for one side of politics keeps alive the dream we will deploy civil powerstations, despite a mountain of cost to get over before it's even legally possible, let alone sensible against LCOE of the existing non-nuclear tech. I think people have forgotten little to no construction skills for nuclear will exist, if the subs are one-lifetime refuel. If its operating skills, we have a reactor at Lucas Heights (for nuclear medicine, its a standard swimming pool research reactor) and we could spin up nuclear engineering courses if we wanted to. So this idea we can sword-to-ploughshare the subs is a bit wierd.

As deals go, for defence, its not terrible. As deals go, value for money, it's pretty terrible in the medium-short term because we're paying and the US and Uk are doing fuck all. As deals go in the long term, its unknowable because anyone who thinks they know 5+ years out is lying.

Like all modern defence forces, Australia is big in Unmanned vehicles, and has work in the air, on ground and under the sea and some people in the defence materials sector argue the big nuke subs is a waste of time, if lessons from Ukraine point to new tech solutions by swarms of devices.

The Chinese say they have worked out how to use LEO satellites and something like geomagnetic anomoly detection to find big subs at sea, the myth of "it's hidden in the ocean" may be exposed inside the next 10 years. Not that anyone with subs will stop having them.

(I'm an armchair admiral like everyone else here and acronyms, model/class ship words, concepts have been freely abused. may contain traces of nuts)