On our national day we must realize that to remain true to our history’s noblest aspect, to extend the realization of the promise of its founding, the nation must cease to exist.
His argument is that Australia was formed when the separate colonies agreed to cede their power to a larger union in order to achieve equal rights and an improved welfare for all. But now we are too selfish to realise that the earth belongs to everyone and that to achieve true equality and to avoid the catastrophe of global warming we must again cede power to a larger union - a world government:
While air, seas, rocks, flowers and fauna of this world are by Nature common to us all, they are not shared by all ...
It seems that only injustice, the product of avarice, itself the outcome of ignorance in both proles and plutocrats, is the lot of the vast bulk of humans, our cousin hominids, and indeed the biosphere.
Our greatest hypocrisy lies in claims that we value egality.
... Until [we learn to be moral] by subsuming our nationhood into the single world polity that both reflects the global realities, and is needed to mitigate the threats facing all peoples, then we are lesser folk than our forebears: smaller in mind and spirit, with withering stature in the world ...
... Just as our nation was formed as a collective, it must dissolve into a greater collective, with fairness to all, not within the borders that must and will disappear, but bounded only by the atmosphere we all breathe.
... we must see all humanity as one people, one polity, one past, one present, one future.
So the message is that to live up to the higher standards of our ancestors we have to dissolve a sovereign Australia.
It's interesting that Dave Bath appeals to an instinctive, intuitive patriotism in his call to abolish Australia. He uses phrases like "our national day," "promise of its founding," "promise of our past," "our history's noblest aspect." Yet the appeal to patriotic feeling is employed against the patria (which reminds me of the way that feminists sometimes appeal to a masculinity they wish to abolish, i.e. they argue that a real man would be willing to give up a distinctively male role).
One problem with Dave Bath's argument is that it doesn't capture the entirety of what our ancestors held as their ideal. For instance, when Alfred Deakin launched his campaign for Federation here in Victoria in 1898 he finished his speech with a poem by William Gay:
From all division let our land be free,
For God has made her one: complete she lies
Within the unbroken circle of the skies,
And round her indivisible the sea
Breaks on her single shore; while only we,
Her foster children, bound with sacred ties
Of one dear blood, one storied enterprise,
Are negligent of her integrity.—
Her seamless garment, at great Mammon's nod,
With hands unfilial we have basely rent,
With petty variance our souls are spent,
And ancient kinship under foot is trod:
O let us rise, united, penitent,
And be one people,—mighty, serving God!
According to the poet, it is the "ancient kinship" shared by the settlers which is a natural source of unity.
So the more traditional form of nationalism, based on a shared ethnicity of some sort (language, ancestry, culture, religion etc) was present at Federation. This traditional form of nationalism was to fall foul of the liberal idea that we are to be regarded as self-defining individuals who must not be impacted by unchosen attributes such as gender or ethnicity.
Therefore, a civic nationalism in which citizenship alone defined national belonging triumphed. Dave Bath recognises that this change took place (and approves of it) when he writes:
We have dropped the torch of early ideals, the only advance being the yet imperfect acceptance of the immateriality of accidents of birth of our fellows: the color of skin, any faith of forbears, the borders within which they first drew breath.
But the newer civic nationalism is inherently unstable. First, citizenship still discriminates - it still places restrictions on the self-realising individual. Therefore, even citizenship distinctions will come to seem unjust, discriminatory, unequal or unfair. This is the path that Dave Bath seems to have followed.
Another weakness of civic nationalism is that the borders of the nation no longer have a logical fixed point. If all you need to do to become an Australian is to agree to certain liberal political values, then any person can potentially be an Australian and any place can potentially be joined to Australia.
This means that if the political elite believe there to be practical advantages to merging an existing nation into a larger entity, they are likely to think it reasonable to do so. Hence the continuing extension of the EU and calls for Australia to merge into a Pacific Union.
Civic nationalism, therefore, isn't likely to last in the long term. Which then leaves the question of what is likely to replace it.