Atonement for sin required sacrifice - paid in the currency of blood - and Gallipoli provided the first real opportunity for Australia to proffer her sons in the quantum that the removal of the stain required.
Historian Robert Hughes noted that the "local imperialists, who believed that Australia could only survive as a vassal of Great Britain, held that the solvent for the birth stain was blood, as much of it as England needed for her wars".
Hughes, an Australian, also suggested Australia embraced Gallipoli with such profound sentiment because, up until 1918, Australia's history had very little to be proud about.
For New Zealand's part, it suffered from an inferiority complex of being Australia's little brother. Australia's forces were some 24,000, three times New Zealand's 8000 contribution (but proportionally, roughly the same) and as such New Zealand invariably played second fiddle to the Australians in most offensives.
The dash and daring displayed by the Australians on the morning of the landing was recorded and lauded by all, and rightly so. However despatches, and history, tended to focus on the larger Australian force at the expense of their smaller colonial brothers.
This inferiority was enforced by a lack of official recognition for gallantry by New Zealand soldiers. The British General commanding the Australians lobbied for and got his men seven Victoria Crosses for the battle at Lone Pine. By comparison, New Zealand's British General, Godley, chose not to forward a number of recommendations for awards - only one New Zealander was awarded a VC for the entire campaign.
Godley saw such bravery not as something to be lauded but rather as behaviour that was expected.
Chris Pugsley, a New Zealand military historian, has observed "we became submerged in an Anzac epic, where the deeds and even the name are synonymous with Australia. That is why today 'The Landing' and 'Lone Pine' and 'the Nek' have a familiar ring to them but 'The Daisy Patch', 'Chunuk Bair' and 'Hill 60' are unknown."
In many ways, Australians have constructed Gallipoli so that they have more to remember whereas New Zealand - until recently - appear to have done the opposite: for them there is more to forget.
In the past 20 years, both countries have been experiencing a renewed enthusiasm around Anzac Day where new generations are claiming and shaping the Anzac myth in their own secular, sacred narrative.
The danger is that war and nationalism are lionised - and sacrifices of the past will be used in support of initiatives for the present.
The greatest honour we can pay the dead is to learn from the past and to never commit ourselves to such barbarity again or, as one old Maori proverb says, "to walk backwards towards the future".
Anton Oliver is the patron for the Coalition for Open Government and former All Black.