Times change and we change with them, as the saying goes. Much the same could be said of warning times: as our strategic circumstances change, so we should reassess the consequences for contingencies that the ADF might be involved in and their associated levels of warning.

Warning time is a key concept. It has a pervasive effect on defence planning, being a strong determinant of the force structure, including the purpose and structure of reserve forces. It is a similar determining factor for the readiness spectrum of the ADF’s force elements and the associated levels of sustainability. At least in theory, it should have a strong effect on defence policy for industry. Perspectives on warning time are integral to the assessment and management of strategic risk. If views on warning time are too optimistic, the nation is subject to an inappropriate level of risk; if too pessimistic, then we incur unnecessary expense with little compensating benefit.

Over most of the past 40 years, Australia has been able to take a relaxed approach to warning time. Starting in the 1970s, the key observation was that the potentially hostile capabilities that might be used against us were at only modest levels. Further, it was difficult to imagine an issue of sufficient weight to cause military action against us to be contemplated. These conclusions led to the concept of the core force and expansion base: the capabilities of the ADF would be sufficient to handle those lesser contingencies that might arise in the shorter term, and be the basis for expansion in the event of serious strategic deterioration in the longer term.

This approach to defence policy accepted that motive and intent could change relatively quickly, given a sufficient catalyst, but that it would take an adversary considerable time—10 to 15 years—to develop the level of capability, including doctrine, necessary to mount a serious assault on Australia. Over the years, the structure and preparedness of the ADF evolved to be consistent with this policy, although the diligence with which these principles were applied tended to depend on the level of defence funding that was available at the time. Development of the force structure also reflected the priority for strong maritime forces and the defence of the sea–air gap to our north. While some elements of the ADF were ready to move within hours, such as counterterrorist forces, most elements were at a more relaxed state of alert, with readiness times varying between weeks, months and, in the case of parts of the reserve forces, years. Training levels and sustainability were influenced as much by the need for the ADF to meet high professional standards as by considerations of warning time.

In our recent paper, Australia’s management of strategic risk in the new era ^[1], Paul Dibb and I argue that times have indeed changed, and that it is now necessary to reassess warning times and the consequences for preparedness and the force structure. The basic proposition is that with the rise of China and its ambitious program of modernisation and expansion of its armed forces, it is no longer the case that potentially hostile forces have only modest levels of capability. Further, these capabilities will continue to increase over the years ahead. This situation takes away the main argument of previous decades that contingencies in the shorter term would necessarily be at a low level and that warning times for more serious contingencies would be long. This is not to ascribe to China (or anyone else) the motive and intent to conduct military operations against Australia; that is a separate argument. But it is to recognise that warning times based on assessments of motive and intent will necessarily be shorter—and more ambiguous—than those based on evidence of the absence of capability, as was so strongly the case in earlier decades.

It is important not to be alarmist: contingencies, least of all serious ones, are not waiting for us around the next corner. Nevertheless, Australia’s new and evolving circumstances will be more demanding. At the very least, the prospect of shorter warning times calls for a thorough review of the readiness and sustainability of the ADF. This review should include the expansion base, reserves and industry in its scope. In our paper, we suggest that areas which need attention for the shorter term include a sustainable surge capacity for round-the-clock operations, munition stocks, fuel resupply (especially in northern Australia), and forward operational bases. Even if the government cavils at the expense of higher levels of preparedness or is otherwise not persuaded by the arguments, Defence should at least identify the steps that would need to be taken to position itself to respond to contingencies within whatever warning time turns out to be available.