The Australian War Memorial's principal historian Dr Peter Stanley has released a paper that claims Japan never planned to invade Australia and the "myth" was promoted by Prime Minister John Curtin as a "motivational device".

"The invasion myth had remained alive for 60 years, abetted by the seeming need of Australians to dramatise their situation in 1942," he said.

"Why can't we as a nation accept that the war the Allies fought was decided far from Australia - North Africa, north-west Europe and above all on the steppes of European Russia," he said. "Why do we appear to want to believe that Australia really was threatened with invasion, that it was attacked."

He said such a desire was "poignant and rather pathetic". Dr Stanley said the bombing of Darwin, the Japanese advance through Papua New Guinea and other military activities around Australia had nothing to do with any invasion plan.