Key Points:

This day 100 years ago, when New Zealand formally ceased to be a colony and was designated a "dominion", citizens of the time were probably little wiser than we are today about what it meant, and not much more interested. New Zealanders have never cared much for constitutional status.

In 1907, they would have noted the Prime Minister, Sir Joseph Ward, had gone to a colonial conference in London where it was agreed the self-governing colonies - Canada, South Africa, Australia and New Zealand - should be styled dominions, and they would quickly have realised the consequent legislation, passed by both Houses of Parliament in July and the subject of a royal proclamation in September, changed nothing besides the official letterhead.

The settler society was already as self-governing as it wanted to be and had been so for 50 years. It decided its own domestic affairs and happily deferred to Britain in foreign policy.

New Zealanders in 1907 still regarded themselves as British, albeit a healthier and hardier breed for their life in the new country. For most it was barely a generation since they or their parents had left Britain by ship and two generations more would refer to the old country as "home".

"Dominion" suited their identity well enough. Two decades later, when imperial conferences of the dominions began to take the next step to complete legislative autonomy, New Zealand was in no hurry. The Statute of Westminster, giving effect to the resolutions of the conferences, was passed by the British Parliament in 1931 but not adopted by this country until 1947.

Even after the word dominion was excised from official letterheads it lived on in the title of the capital's morning newspaper and the annual conferences of the National Party and Federated Farmers. In conservative circles there is even a suggestion that today, Dominion Day, might be preferable to February 6 for the annual national celebration.

That suggestion would have surprised legislators of 1907, who did not think their steps worth a public holiday. If a national day should mark the achievement of full constitutional independence ours would fall on November 25, the day Parliament ratified the Statute of Westminster.

But that belated act represents a reluctant nationhood and independence in name only. Economically New Zealand remained dependent on Britain until the 1970s when the UK, rather than this country, initiated change by entering the European market.

Like a lucky, last-born child of a comfortable family this country has had to be forced to fend for itself. While its good fortune is nothing to regret, it is not a strong ground for national celebration either. There is no harm in the Government's decision to mark today's centenary with a symposium at Parliament but the true significance of Dominion Day could not sustain an annual effort let alone be the basis of an alternative national holiday.

Nor could November 25 or any other date that might be invested with national importance so long after the event. The truth is we have a national day with more meaning than any substitute could be given. The national significance of the Treaty of Waitangi was not widely acknowledged for 133 years after its signing but its neglect has been rectified since. It may not be a happy anniversary for a long while yet but it offers this country more meaning, challenge, distinction and achievement than any of our uncontested, unexcited steps to independence.