My view is that we’re sleepwalking. Until recently, we’ve always had the view that there are no military powers in Australia’s region of primary strategic interest capable of invading us without a very significant period of warning time.
But that clearly has changed now. Many countries in our region, but especially China, are developing long range power projection that can reach Australia.
And with China’s militarization of bases in the South China Sea, China’s power projection capability is 1,400 kilometers closer to the North of Australia.
We’re now facing very short warning times when it comes to military capabilities which directly threaten our territory for the first time since the Second World War, because that’s what China has built up and the trajectory they are on.
As you know from your time in Australia, the strategic community is now discussing this challenge and how to wrestle with the problems posed by the new strategic situation.
The last few years really haven't changed things enough to justify this kind of "transition" talk.
Australia is a low-population island democracy far from traditional and new "Western" states. It needs submarines and air power as the primary means of keeping enemies away from the continent. That and a small but good ground force capable of working with allies who can reach them are needed to leverage foreign--especially American--help. That's basically what I noted over ten years ago:
Australia needs to defend at sea, for if any enemy intent on waging war makes it to shore, Australia would need a huge army to defend their nation/continent. That's not going to happen, although it wouldn't hurt the Australians to organize light infantry local defense forces to fight until the good but tiny army arrives to fight any enemy force that does make it ashore.
But the basic defense will be aircraft and submarines that could attack enemy ships on the way to assault Australia. Even if the enemy had a couple carriers, the F-35s with their stealth abilities would be a good weapon to sink them and shoot down any aircraft they carry. The submarines would be able to operate against the invasion fleet, too, even in the face of enemy naval superiority.
The frigates would be best for leveraging allied help to sail with either American or possibly Indian ships to fight a common foe. Alone against a major enemy fleet they'd be fairly worthless.
What is the new strategic situation? The only thing that has changed is that the Chinese threat is continuing to grow. That wasn't foreseen?
And America is stepping up by adding air power to Australia:
Thousands of U.S. Marines on an Australian Army base this summer might be the most visible example of America’s growing military presence Down Under. But the nations’ air forces are growing equally close under a lesser-known program known as Enhanced Air Cooperation, or EAC.
The initiative, which kicked off in 2017, focused this year on fifth-generation fighter integration, aero-medical evacuation and aircraft maintenance. It involved U.S. F-22 Raptor, F-35B Lightning II, F-16 Fighting Falcon and F-15 Eagle fighters, B-52 strategic bombers and C-130J Super Hercules transports, according to the Australian Defence Force’s website.
As I said a decade ago, we'll see if Australia funds their defense needs. One effect of that kind of an effort is that America thinks Australia is worth partnering with. Talk at that first link about poorly protected bases in the north and west are issues of funding and not strategic confusion with a new threat rising.
Or the Australians can just give up and suck up to China, I suppose. Hey, Australians started out as prisoners dumped on that far shore. I guess they can learn to endure their new Chinese prison guards if they want. I hope that isn't the choice Australia makes.
UPDATE: I have no problem if America sells the B-21 bomber to Australia. If they are that worried about the range issue of the F-35, go for it. I assume that we wouldn't equip the B-21 for Australia as we equip our own. That's standard procedure. But the basic air frame should certainly be for sale to a trusted ally.