Brisbane Line

Although a plan to prioritise defence in the vital industrial regions between Brisbane and Melbourne in the event of invasion had been proposed in February 1942, it was rejected by Labor Prime Minister John Curtin and the Australian War Cabinet.

[1] Mackay had previously been instructed to prioritise the regions around Sydney and Newcastle, with Darwin as a secondary priority, and had to consider the fact that a large portion of Australia's military and naval forces were deployed overseas.

[1] Ward's theory was based on an incomplete understanding of this plan[citation needed] (which had been submitted to and rejected by Ward's own government, catered for the defence of strategic northern locations, including Darwin and Townsville, and instead of simply abandoning the rest of the country to the Japanese, advocated a scorched earth policy and guerrilla warfare to slow invaders until other forces could be deployed), along with public knowledge of evacuation plans for regions of Queensland (which, instead of a total evacuation south, was to clear potential battle sites of civilians).

[1][2] The royal commission and the Brisbane Line controversy contributed to Curtin and the Labor Party winning the 1943 federal election by a significant margin, but Ward was effectively demoted by being assigned the portfolios of Transport (the assets of which were under direct Army control) and External Territories (most of which had been captured by the Japanese).

[7] In his memoir, Reminiscences, MacArthur claims that the Australian military had proposed designating a line roughly following the Darling River as the focus of defence during the expected Japanese invasion of Australia.