How are they linked, you might well ask.

The government is planning a plebiscite next year on marriage equality. Abetz argued that whatever the result, federal MPs should still be able to follow their conscience on how they vote on the subsequent legislation when it comes before the Parliament.

He also argues that if they felt that a majority of their constituents opposed marriage equality (even if an overall Australian majority were in favour) they should feel free to oppose the subsequent legislation so they can represent their constituents' views.

Others on the right of the Coalition agree with him. Others still, notably Senator Arthur Sinodinis, argue that MPs should respect the people's will and if a majority in the plebiscite approves marriage equality they should vote for it in the Parliament.

The Abetz position shows that those on the right of the Coalition will simply ignore the result of any plebiscite on marriage equality or the republic and pose whatever arguments they can muster for doing so.

Republicans be warned. A plebiscite majority on Australia becoming a republic will simply be ignored by constitutional monarchists and anyone else who dislikes any element of the final constitutional wording.

So even if an overwhelming majority vote Yes in a non-binding plebiscite, the final binding referendum to change the wording of the Constitution could easily be lost.

The republican movement thinks that a Yes vote in a plebiscite would have such overwhelming moral force that any subsequent referendum to put a republican model into the Constitution would be equally approved.

Well, Abetz's comments this week show how naïve that view is. Those opposing change don't give up.

The idea of a non-binding plebiscite is completely daft.

So what if a majority say, "We like motherhood"? Come a binding referendum, they will acknowledge motherhood is good, but argue that this model is Cinderella's step-mother and should be opposed.

The republican movement should abandon the plebiscite idea. It will achieve nothing. A majority Yes vote will have all the persuasive and moral force among constitutional monarchists and those who oppose to the model on offer as a mobile phone signal in the Simpson Desert.

The way they are going about it is asking for another referendum defeat.

The plebiscite on marriage equality is an equally misguided waste of money. It was only an Abbott stalling tactic in the first place.

I agree with Abetz. This is a matter for members of Parliament. The constitutional position on marriage equality is clear. It was made clear in the ACT marriage-equality case that the Federal Parliament has the running on marriage and that the word "marriage" in the Constitution includes marriage between people of the same sex.

The logical extension of Abetz's position is that the plebiscite is a waste of time if he thinks MPs have the right to ignore it.

In any event, the Constitution does not provide for binding votes to create legislation. Only the Parliament can legislate. The Constitution provides for binding votes only for changes to the Constitution itself.

So with marriage equality, the Parliament should just get on and legislate for it. Why waste $150 million on a plebiscite that will tell us what we already know through opinion polls – that a large majority is in favour.

Why waste $150 million on a republic plebiscite that will tell us what we already know – that a majority is in favour but are unsure about details? And it will not change one letter of the Constitution.

Plebiscites are only useful when you want an indication of opinion about the relative support among several options. The 1977 national anthem plebiscite was a good example. The New Zealand process for deciding its flag is another.

In New Zealand's case a vote was held last year to choose one of five potential new flags. The winner is to be pitted against the existing flag in a second vote this year.

This would be a good model for the republic. First, sort out several models with new wording for the Constitution. Say, a directly elected president; a president approved by a two-thirds majority of Federal Parliament; a president appointed by the Prime Minister; and no doubt some others.

They would put in a preferential non-binding vote. The winner would be pitted against the existing monarchical system in a binding referendum to change the Constitution.

That first non-binding plebiscite would then have some moral force. The message to constitutional monarchists would be: "Even if you do not want a republic, at least make your view clear on what sort of republic you want in the event that a majority of your compatriots do want one."

Also, republicans could argue that the people have approved this model, so republicans who do not like some aspects of the model should not urge a No vote in the hope that their preferred model will one day get up.

History tells us what that leads to. The misguided urging of a No vote in 1999 by direct-election republicans Ted Mack and Phil Cleary in the hope their model would get a run later has led to a 20-year delay in the republican cause. Well done, idiots.

Incidentally, the reaction by Prime Minister Malcolm Turnbull to this week's declaration for a republic by all but one of Australia's premiers and chief ministers shows the dismal state of political leadership in Australia today.

Here we are. Every state and territory leader is in favour (even WA Premier Colin Barnett who did not sign the declaration agrees ultimately to a republic). The leaders of the three main political parties federally are in favour. Opinion polls now have a majority of the public in favour.

Yet between them, our impotent political leaders cannot muster a method to deliver what most Australians want – to expunge the hereditary monarchy from our Constitution.

There has never been a more frustrating time to be an Australian republican.

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