The latest defence white paper will fail again, unless there is a change of heart, writes HUGH WHITE.

Here we go again. The Abbott government is starting work on another new defence white paper. Normally these things come along about once a decade, but we have already had two in the past four years.

The last was published only nine months ago.

Both failed utterly to deliver a workable plan for Australia's defence.

So Tony Abbott is right to order another - as long as it does not turn out to be just another failure like the last two.

A successful white paper must align what we want our armed forces to be able to do with the military capabilities we plan to buy and the money we plan to spend.

So to get it right this time the government will need to commit enough to fund the forces needed to achieve the strategic objectives they set.

They will get it wrong if they don't commit enough for the forces they plan, or those forces cannot achieve the objectives they set, or both.

The last two white papers failed on both counts. Most obviously they failed to commit enough money. But, more importantly, they failed to identify what basic tasks the defence force is supposed to be able to do, and what it needs to be able to do it.

The new white paper will fail, too, unless it addresses both these problems. And it must start by deciding and defining as clearly as possible what we want our defence forces to be able to do. Those decisions must themselves be based on judgments about the kinds of threats we might face and how serious they might be, and we must look ahead several decades because major capabilities take decades to deliver.

This is never easy, but it is especially hard right now.

After four decades of relative stability Australia's strategic environment today is uncertain, and the range of threats we might face in coming decades is growing fast.

That is all because of mounting questions about America's role in Asia.

Since the mid 1970s, after Nixon had opened US relations with China, Australian defence policy has been framed by the simple fact that America has been the uncontested dominant power in Asia.

That has made Asia very secure, and has put a low ceiling over the kinds of military threats Australia might face, and limited what we might need our forces to do either by themselves or in support of America. And that, in turn, has limited the capabilities we have needed and the money we have spent.

That is why the defence budget has shrunk so low.

The key question for Australian defence policy today - the question the last two white papers failed to address - is whether that can last.

Can we continue to assume that uncontested American primacy will remain the foundation of Asia's strategic order and the determinant of Australia's defence needs for the next three or four decades?

If we can, Australia's defence needs are low and our defence policy is easy.

We can keep building the same kinds of forces we have had for decades, and spending the same kind of money. But, if we cannot make that assumption, then everything becomes much harder.

We would have to consider a much higher chance that we would have to fend off bigger threats without US help, or that we would have to provide much stronger military support to America if it faces a big conflict in Asia, or both. If so, the kinds of capabilities we have had until now, and the money we have committed to build and sustain them, look woefully insufficient.

No prize for guessing what the government - any government - would like to believe. But the evidence is all the other way.

As China's power grows, American primacy is no longer uncontested, and the old Asian order built on uncontested US primacy is already passing away.

That doesn't mean conflict in Asia is inevitable, but it makes the risk much higher.

It doesn't guarantee that America will scale back its role in Asia, but that becomes much more likely, too. These are precisely the kinds of risks defence policy must address.

The last two white papers failed because the ministers responsible for them could not bring themselves to face this and acknowledge Australia's new strategic reality.

They could see that some things were changing - hence Kevin Rudd's bald statements about a China threat and his commitment, in his 2009 white paper, to build more submarines. But they fell back on complacent assumptions the old status quo would last for ever, so nothing serious was done. Rudd's extra submarines were not planned to appear before 2040.

The Abbott government shows signs of going the same way. In their statements since taking office, Tony Abbott and Julie Bishop seem to cling even harder than Kevin Rudd and Julia Gillard did to the agreeable idea that Asia can be transformed economically by the biggest shift in wealth and power in history, without changes to its political and strategic order.

Unless they have the courage to start questioning that assumption, and to follow through on what that means for Australia's strategic objectives, capability needs and defence funding, the new White Paper will fail as badly as the last two, and for the same reasons.

Hugh White is professor of strategic studies in the Strategic and Defence Studies Centre, ANU. He was the principal author of the 2000 defence white paper.

This story also appeared in Fairfax media.