Australia's military has begun to transform itself for a new age of warfare, with the federal government on Monday endorsing the most significant shift in Australia's defence strategy since the 1980s.
Former ADF chief Sir Angus Houston and former defence minister Stephen Smith were tasked with assessing the nation's defences, and deemed the nation was not ready for the new military age — dubbed the "missile age" — the world had entered and it needed urgent re-arming.
Some of Defence's strategy will be kept secret, some has not yet been announced, and some is not yet known, but here is what we have learned from the landmark Defence Strategic Review.
Australia has entered the 'missile age'
For more than three decades, Australia's military has focused on what the reviewers termed "lower-level threats", such as terrorism and conflicts in the Middle East.
But the Defence Strategic Review spells out that the world has changed, with China amassing the greatest military build-up of any nation since World War II, and that Australia is not equipped to face it alone.
Modern military technologies have given more countries the power to reach out and strike further than they could before. And the review says the proliferation of long-range precision strike weapons has "radically reduced" Australia's natural geographic advantage.
In addition, Defence's long-held assumption that Australia would have about a decade to prepare for conflict on its shores can no longer be relied upon.
While the review maintains that the risk of invasion is at present a "remote possibility", of greater concern are threats of military force and coercion that do not require invasion, including against Australia's trade and supply routes.
The review determined the rise of the "missile age" had removed the "comfort of distance" for Australia.
Australia's north must be 'hardened'
In response to a growing focus on the Indo-Pacific, the federal government says it will "harden the north", re-prioritising defence spending on developing northern bases and ports, and growing Australia's ability to strike further out from its northern shores.
All of Australia's military "domains" — that is, army, navy, air force, cyber and space — will be more closely integrated, but it is the nation's land forces that will face the most significant change.
The army had been building land capabilities, including by adding hundreds of armoured infantry vehicles, which was to be the most expensive project in its history.
That will be scrapped in favour of Australia building its own long-range strike force — in part to give Australia the power to project into its seas by itself, rather than relying on allies such as the United States.
However, Australia will also develop its "statecraft", and seek to strengthen diplomatic and military ties in the region, as well as its ties with nations such as the US, India and Japan.
Defence Industry Minister Pat Conroy said once those changes had been made, the army would shift from being able to reach out 40 kilometres to a range of almost 1,000 kilometres.
Australia's navy will also be reshaped, though decisions surrounding that will be made later this year following a review by the US Navy Vice Admiral William H Hilarides.
With the acquisition of nuclear-powered submarines in the next decade, the role for other vessels will shift, and so the navy is expected to be reshaped to ensure surface vessels are still efficient.
Meanwhile, a number of barracks upgrades and other infrastructure projects considered a lower priority have been pushed back or abandoned in favour of a rapid upgrade to Australia's northern bases.
Defence will take up an even greater share of the budget
We don't know how much this is all going to cost. Although, with a federal budget just weeks away, we will soon know a lot more.
The federal government won't set a minimum spending target tied to GDP — a common target that defence spending is often measured against — but Defence Minister Richard Marles said spending on Australia's defences was certain to increase in the next decade over and above spending increases already committed to by the previous government.
The government will spend $19 billion implementing the proposals from the Defence Strategic Review, though it will recoup some of those costs through $7.8 billion of downgraded and scrapped projects.
That cost will be on top of the $270 billion price tag the former government placed on defence in 2020 for the decade ahead, which included employing thousands more workers, more potent strike weapons and cyber capabilities.
On top of that was the deal struck with the United States and the United Kingdom for Australia to acquire nuclear-powered submarines, which will cost up to $368 billion over the next 30 years.
The reviewers criticised the former government for committing to $42 billion worth of unfunded defence projects since 2020 that the government would have to find money for.
Climate change threatening to overwhelm Defence
One of Defence's key roles in recent years has been assisting in natural disaster responses, first during the Black Summer bushfires, then during the pandemic, particularly in aged care, and in the last year during floods in NSW and Queensland — as well as assisting in a number of humanitarian operations overseas.
But the Defence Strategic Review says that is straining Defence's resources, putting Australia's military at risk of being "overwhelmed" and undermining its primary objective of defending Australia.
It warned state governments and local councils they would have to go it alone except in the worst disasters.
The prime minister said in a press conference there would need to be "further consideration" of how Australia would respond to disasters without the ADF.
The emergency management minister has flagged the possibility of establishing a semi-professional stand-by workforce that would be able to respond to natural disasters.
