Given he was the principal author of the 2000 Defence White Paper, it is reassuring to know that Hugh White agrees with me that Australian strategic policy needs a rethink, even if he is not persuaded by all of my prescriptions. So, in the spirit of a full and frank debate about what needs to be done, let me respond to Hugh's observations and counterpoints to my Lowy Analysis paper, Full-Spectrum Defence: Re-thinking the Fundamentals of Australian Defence Strategy.

To begin with, I agree the ADF should be structured to respond to threats from other countries' armed forces. Defending against such threats must be a primary mission, and I have not argued otherwise. But the military threats we confront today are more diverse and interlocked than ever before. They are increasingly playing out over five domains (land, sea, air, space and cyber) rather than just land, sea and air. And the growing military prowess and information-warfare capabilities of non-state actors warrants greater consideration in our strategy and force structure calculations.

Consider Russia's involvement in Ukraine as an example of what future armed conflict between states might look like: there was no declaration of war and no readily identifiable Russian force streaming into eastern Ukraine with pennants flying. Instead, Moscow opted for plausible deniability, using a mix of irregular and conventional forces supported by an effective information-warfare campaign, including cyber attacks, to achieve its initial political and military objectives.

Our strategic planners need to think through the implications for the ADF. I look forward to seeing their conclusions in the forthcoming white paper.

Yes, I do cast my net wider than Hugh in thinking about the variables that should shape the future ADF. That's because the ADF is required by governments to do much more than defend Australian territory against a particular kind of military attack coming from a specific location or direction. Future governments will expect a richer suite of military options from the ADF than ever before, including an enhanced capacity to deploy and sustain significant forces at considerable distance from Australian shores in defence of our interests, not just our territory. So our strategic reach must be longer, and our capacity for autonomous operations – what we used to call self-reliance – correspondingly greater. All the more so in a post-American world.

Which leads me to Hugh's point about the Middle East.

As strategists, we can both have our views about the wisdom or desirability of particular deployments, or whether military force is the appropriate response to a particular problem. But the reality is that Australian governments of all political persuasions have consistently committed the ADF to military operations well beyond our immediate neighbourhood, and not just to the Middle East.

I have no doubt this will continue to be the case. It is therefore incumbent on defence planners to make the ADF as agile and deployable as possible within budgetary constraints so that our defence force can confidently operate wherever it is deployed with the necessary protection, firepower and C4ISR. And that includes the Middle East.

It is sometimes argued that designing a versatile force reduces our capacity to defend Australia, or that a force optimised for such a task can do everything else pretty well. I don't buy either proposition. A far better approach is to identify the core tasks required of the ADF and design an optimal defence force to meet all of them. That is why the new amphibious ships — so versatile and useable in virtually all the ADF's core tasks — are so useful.

Perhaps I have not been as clear as I should in my writing about future threats because I am in furious agreement with Hugh that the future does not always resemble the past. But my take is a little different. In allowing for a different strategic future, one ought not to assume that the past, particularly the recent past, has no relevance. Defence planners should ask what, in the recent past, is likely to continue and what may change. My answer to the first part of the question is that messy, hybrid irregular conflicts like Ukraine, Afghanistan and Iraq/Syria are going to continue and that the form of warfare they represent has direct implications for the ADF.

As to what may change, without pretending to be an oracle, my money would be on the real possibility of future interstate conflict in the western Pacific, further dangerous mutations of transnational terrorism, the growing importance of the cyber and outer space domains, and the automation of weapons platforms and systems driven by breakthroughs in artificial intelligence and robotics.

As a former defence intelligence analyst, I am the last person to denigrate the value of horizon scanning or, as we used to call it, 'peering into the future'. My concern is about using speculative long term assessments about the future strategic environment to justify force structure and planning decisions that lock us into systems we have to live with for 30 to 50 years when technological change is continuing to accelerate. Hence my argument about shortening the timeframes for acquisition decisions and moving towards acquiring capabilities that are more flexible, disposable, usable and upgradeable.

Ah yes, but what about the money? I suspect we could use several megabytes of blogging space talking about money, but let me be brief.

I made a deliberate choice not to talk about money in this Lowy Analysis, and not just  because of space limitations. There is virtue in having a first-principles discussion about strategy unencumbered by budgetary considerations, since this encourages clear thinking about the appropriate objectives of strategic policy and ADF priorities.

Two points about money. The first is that defence planners seldom, if ever, have certainty about future government outlays. So they do what any sensible person would do and make reasonable assumptions about likely future spending based on past experience, current commitments and the forward estimates.

But no matter how big or small the actual budget, every budgetary process involves trade-offs between competing priorities. In this sense, defence is no different from any business or other government department. What is important, however, is the efficacy of the process for allocating resources. My argument is that the current process is flawed because resource decisions are far too often arbitrary and/or distorted by bureaucratic or political interference rather than being the result of a considered strategic risk-assessment process.

My other observation is that defence planners should not try to artificially situate their military appreciations and force structure options by trying to second guess how much money the government of the day is likely to allocate to defence.

Most government ministers I have talked to over the years maintain that what they want from the Defence Department is costed force-structure options so that they can make informed decisions about the appropriate level of funding. To quote one senior minister, 'Defence needs to tell us what it wants and why. It is the government's task to decide what is justifiable and affordable.'

Finally, if Hugh feels so inclined, it would be helpful to hear whether he sees irregular warfare as the dominant form of future conflict, both between and within states, and whether our force structure determinants have any redeeming value as strategic planning constructs? And if he still believes our defence strategy should be a maritime strategy, how does he see a three-domain construct (land, sea and air) encapsulating the five-domain warfare of the future?

Photo courtesy of the Defence Department.