High Quality Content by WIKIPEDIA articles! In early 1942 elements of the Imperial Japanese Navy (IJN) proposed an invasion of Australia. This proposal was opposed by the Japanese Army and was rejected in favour of a policy of attacking Midway Island and isolating Australia from the United States by advancing through the South Pacific.Japan's success in the early months of the Pacific War led elements of the IJN to propose invading Australia. In December 1941 the Navy proposed including an invasion of Northern Australia as one of Japan's 'stage two' war objectives after South-East Asia was conquered. proposed including an invasion of Northern Australia as one of Japan's 'stage two' war objectives after South-East Asia was conquered. This proposal was most strongly pushed by Captain Sadatoshi Tomioka, the head of the Navy General Staff's Planning section, on the grounds that the United States was likely to use Australia as a base to launch a counter-offensive in the South-West Pacific.