Value of ships/projection platforms is how it mediates geography and technology and economy. Pacific/Atlantic ocean offering US 10,000km+ buffer on each side means historically, US HAS to rely on mobile platforms (and forward basing) to hull sufficient munitions in theatre across the pond due to both technologic and economic limitations, i.e. there technologically was no accurate long range fire, no sufficient ISR (pre space / gps) that would enable medium / long range strikes, and economically to deliver accurate munitions at scale, shooters needed to be close / right there.

But being "right there" is a consequence, of HAVING to be right there. Cruise missiles extended "right there" to standoff ranges of 1000-2000km, but we're also in age of meter level CEP 5000km IRBMs/AShMs, shooters don't have to be "right there" anymore. IMO important not to conflate with being able to shoot something, for needing to be "right there" to shoot something. If anything you want to be no where near where the shooting happens. Words like "persistence", "presence", "projection" gets abused as proxy for (sea) control, especially useful propaganda/signalling tool during peacetime (look, we're right there), but the actual coercive power during peacetime or control during shooting war is done by the munitions (and sensors to direct them). Modern day rocketry + persistent space ISR can like cover what historically needed carriers/subs to cover, especially for AU considerations (IRBM range) hence value proposition of SSGNs is different, which is why I question the AUKUS sales pitch from warfighting capability perspective. Land based rocketry also much more flexible than committing to SSGNs + cheaper shorter range cruise missiles ... that requires subs to operate closer to their target, using likely interceptable / defeatable munitions (since the subsurface gamble is stealth lets you shiv with ~100 smaller cruise missiles up close vs ~20 hypersonics from far away), but if munitions doesn't measure up, might as well not be in theatre in the first place, and chance of retrofitting subs around larger extended range munitions unlikely, so it's multi decade gamble. This is not to mention the complexity of subsurface kill chain / communicating underwater.

Meanwhile a PLARF TEL popping out of a tunnel in Hainan to launch a mach10 missile can reach Darwin in 20 minutes. AKA no defense/offense dichotomy, rocketforce can also do anti area/access denial, i.e. when targetting Guam, forward bases in 1IC. 360B buys a lot of irbms, i.e. everything up to 1-2IC/Australia north coast might as well as be "right there" from PRC theatre/IRBM perspective. Recipriocally AU can also do this from upside down land. Is AU better served with risking forward positioned SSGN with 100 x 2000 km cruise missile sized cells or for same price, 400 x 5000km land based hypersonics that can cover the theatre, plus distributed for more survivablity. IMO Australia has options other than SSGN to bring the fight north 5000km versus US trying to bring the fight west 10000km. Especially considering the maritime choke points across 1IC.

Question is: which options better for AU to spend 360B to have some sort of medium / long range fires into SCS / IndoPac theatre. Considering SSGNs will lock in procurement for 50+ years. Especially considering hulls won't be in water in meaningful numbers for 20+ years while PRC ASW capablities are growing. Meanwhile, PLA is also coordinating land, sea, air at likely greater relative scale than what US+co are projected to bring in theatre, which increases challenges of subsurface survivability with time. IMO all the trendlines are against locking in on eggs in basket of expensive subsurface. It's gamble on purely warfighting value, which cannot be seperated from procurement economics, as in opportunity cost of what other warfighting capabilities that 360B can buy, and sustainment economics, as in SSGNs are such big investments that it will constrain future procurement options. Decommissioning nuclear will make even divestment hard.

My feeling is AU better off with some IAPs for near shore defense, and missiles / B21s for long range fires / cheaper per unit procurements that enables future pivot. But as expensive as AUKUS is, on paper it has more domestic $$$ potential, but strategically bad gamble.