Eight decades after the end of World War II, history’s largest conflict still has lessons for Australia.

Among the most important is that we must expect large-scale mobilisation. Today, despite our population being four times greater than in 1939 to 1945, we would struggle to achieve anything like the intensity of the mobilisation we achieved then.

In a radio address on 16 February 1942, prime minister John Curtin spoke of the ‘Battle for Australia' the day after the fall of Singapore. As recently as 6 December 1941, there had been obvious tensions (including Japanese occupation of Manchuria and French Indochina) but overall peace in the Pacific. The multi-pronged attack on 7 December (eastern Pacific time) almost simultaneously hit the US Pacific Fleet in Pearl Harbour, the British Hong Kong Garrison and US bases in the Philippines.

Few expected Hong Kong, Manila and Singapore to fall in a little more than two months. There are many lessons to be learned, but an obvious one is organising mobilisation in uncertain times with major conflict in the Indo-Pacific.

Australia then had about 7 million people, of whom almost 1 million eventually enlisted.

We hope no threat to the Australian mainland may again come to pass. However, a study of WWII would find similar sentiment among Australians before the shocking fall of France in June 1940, less than two years before we found ourselves not just supporting a distant war effort but in a national emergency.

Australia would struggle to put even 500,000 in uniform and train them within three years, compared with the present Australian Defence Force uniformed workforce of 90,000, including reserves.

Some may scoff at the number of 500,000 for a technology-heavy force in the 21st century. However, deterring an enemy, protecting population centres and vital assets, storing and distributing munitions and materiel, and patrolling Australia’s vast land mass and approaching waters would require enormous expansion of the ADF.

Moreover, we will still need substantial army reserves in sizeable numbers to discourage enemy thoughts of fifth-column operations or even landings. And we should expect to provide workforces for likely extensive staging and basing support for allied forces.

Much of this is observable in WWII experience.

Mobilisation will be one of many issues to be discussed in the Royal Australian Artillery Historical Company’s 2026 seminar series, which is titled ‘Firepower: Lessons from World War II’ and will be held in Melbourne, Brisbane, Adelaide and Canberra over the coming year.

Major factors in getting people into uniform would include enlarging the recruitment apparatus, providing recruits with equipment and training them. A particular problem would be public support.

At the outbreak of WWII, men of military age were familiar with the idea of compulsory service. No Australian of suitable age is now, so creating public support for it would be hard.

To understand the challenges we could soon face, let’s begin by studying how we handled them in WWII.