Key not only supports such a change but he is personally advocating incorporating the silver fern, an iconic NZ emblem, into a new flag on a black background. He will now consult senior ministerial colleagues with a view to holding a referendum at the same time as the next election, due later this year. According to Key, there must be a referendum rather than an act of parliament because it is a ''constitutional'' issue in a general sense. He reckons New Zealanders are split 50-50 on this change, but his suggestion has received support from several other party leaders.

John Blaxland's article advocating changing the Australian flag ("Flying the flag for a fresh start", Forum, February 1, p4) was explicitly published in this context. But he gives little consideration in this article to the political dynamics of such a change, relying on the power of his arguments, though recognising that "opposition [to change] is too strong to see it replaced by bland offerings".

He also notes that such a change is not intrinsically linked to republicanism. Nevertheless, looking at these two issues together clarifies the similarities and differences between them.

The two questions have been linked at times by public opinion analysts, such as the Australian Election Study at the Australian National University, which has portrayed attitudes to the Queen, flag and republic as a family of issues to be reported on together. These studies have shown changing the flag to have much less support than changing to a republic. In 1998, for instance, just before the republican referendum, 39 per cent supported changing the flag, while 66 per cent supported a republic. That referendum failed. So advocates of changing the flag have the job ahead of them.

The two questions have also been linked by monarchists and some republicans. The Australian Republican Movement deliberately does not. It is a single-issue organisation. Monarchists have long tried to associate ARM republicans with what they saw as the more unpopular issue of changing the flag. In fact, the movement to change the Australian flag has always had its own leaders and organisations, such as Harold Scruby and AusFlag, and its own momentum. It has had its own historians and flag designers.

The similarities are fewer than the differences. Most significantly, they are both part of the debate about the place of tradition, especially British tradition, in modern Australia. They are both about the politics of identity, though the flag is even more clearly about symbolism. Neither issue can escape balancing their concerns with recognition of Australian indigenous identity. Finally, new flag advocates such as Blaxland are immediately faced with finding agreement on the details of a replacement flag just as republicans are quizzed on republican models.

Any debate about a new Australian flag should take into account several major differences. The most important is that it is not tied into the Australian system of government as laid out in the constitution. This means that critics of change can't invoke any possible flow-on effects to federal-state relations, social instability, power relations between presidents and prime ministers and the powers of a new president.

These complexities have become a staple of monarchy-republic debates over the past 20 years in Australia to the general detriment of the republican cause. At the very least, even when they have been clarified, such allegations have clouded the issue and made the task of republican advocates more difficult in the public arena. Advocates of a flag change should be spared all these issues.

The flag issue is simpler in other ways. This is why Key could even consider having a referendum at such short notice (less than a year) while both the republic referendum and the forthcoming indigenous recognition referendum in Australia have involved years of preparatory work and extensive public education campaigns.

One way in which a flag debate is simpler is that it has the advantage of being strikingly visual. It is therefore able to be visualised in campaign advertising on both sides. The existing flag can be compared with one or more alternatives without too many hidden meanings. Voters can then be asked to choose between clear alternatives, just as voters were able to vote on alternative national anthems that could be played and sung.

Other referendum campaigns contain visual elements as a way of trying to explain the issues at stake. The republic education campaign did this ineffectively and the indigenous recognition issue will try to improve on that. But they are no match for showing alternative flags.

This is not to say that in a flag vote, like the one proposed in New Zealand, there will not be debate about history, meaning and values as incorporated in alternative flags. There certainly will be. Generic attitudes towards tradition and change will loom large. But a flag vote should be more straightforward even if it is just as intense, perhaps more intense. That is not to say changing a flag is an easier exercise; just that the choices are more straightforward.

Australians should watch what happens in New Zealand with interest because there will be flow-on effects; our two flags would no longer be similar. Key may be trying to move too quickly, especially if the community demands public consultation about alternatives rather than accepting a choice between the status quo and the silver fern.

John Warhurst is an emeritus professor of political science at the Australian National University and former chair of the Australian Republican Movement.

John.Warhurst@anu.edu.au