John Hewson lost the unloseable 1993 election because he proposed a GST. In 1998, John Howard turned his near record 1996 majority into losing the popular two-party preferred vote and almost the election.

Good policy subjected to the blowtorch of scare. It would be terrific if Australian politicians at all levels, commentators, shock jocks and others could have a mature debate about the federation and tax, including the GST.

Labor squibbed it. It refused to even allow the GST to be considered in the Henry Tax Review. What is the point of having a tax review if you rule out discussion on one of the most important taxes in the revenue mix. That is hardly being mature.

And barely a couple of minutes after his call for a mature debate we got this from Abbott: "The GST is a matter for the states but certainly it is something that will all be looked at as part of the federation reform process and as part of the tax reform process."

That is hardly mature. It is not even truthful. The GST is not "a matter for the states". Indeed, Section 90 of the constitution makes it clear that the imposition of excise duties (such as the GST) are the exclusive province of the Commonwealth. In other words, far from being a "matter for the states", the constitution says it cannot be a matter for the states.

Only the Commonwealth can impose a GST. Yes, it can hand the proceeds to the states, but it can only be levied through Commonwealth legislation.

A mature debate would not sink to the ritual Commonwealth-states blame game – blaming each other for the nasties and shortfalls in service delivery or funding.

In May, Abbott tried the same thing. He said of the states: "If they want to change the GST, that's certainly something that they can put on the table as part of the federation white paper process. As far as I'm concerned, I have no plans to change the GST. I want taxes to be lower, simpler and fairer ... My opinion is that we pay more than enough tax already and we have got to, over time, get taxes down".

Well, "lower, simpler and fairer" are contradictory. The lower taxes are, the less fair they are because there is less to redistribute to ensure equality of opportunity. And whose taxes are lowered – higher or lower earners? The simpler taxes are, the less fair they are. Our present simple four-step income tax table is an outrage to fairness.

So some mature debate on tax is certainly needed. And some constructive persuasion is needed. If the income tax system is not changed, many people on quite modest incomes will be pushed into higher tax brackets by the effect of inflation alone. This would not be fair. It would be far better to increase the GST and widen its catch. But again we need mature debate.

Anyone who proposes the GST be widened to cover education, health and rent would, without persuasive debate, be denounced as a foe of the downtrodden. But the reverse is true. Why not impose the GST on private-school fees? Why not impose the GST on massive amounts of money spent on pseudo health – alternative medicine and the like? Why not impose the GST on unprocessed foods? Usually people on higher incomes are the main consumers of these things.

The money raised could be used to rescale the income tax rates which will otherwise hit people earning just $37,000 a year. A raised and widened GST would result in a fairer tax system.

Why not impose the GST on rents? Existing leases, with rent stated, would ensure landlords, not tenants, would have to pay the GST. Market forces would ensure that when leases expired, rent increases to counteract the GST would be counterproductive.

And yes, let's increase the rate to 15 per cent. The myth is that the GST is paid by average Jane Does. This is because it seems to be widely imposed upon everything Jane Doe buys,

But a mature debate would ensure that the electorate understands the true nature of the GST. It is not just a 10 per cent slug (or 15 per cent slug if it goes up) upon everything Jane Doe buys.

Rather it is a tax on all the value added as a good or service gets produced. All of the people on the way have to pay a tax on the value they add. It ensures that all businesses and all sole traders at least pay some tax, however rich they are, even if artful income tax advisers ensure they pay precious little income tax.

A mature debate would result in an increase of the GST to 12.5 per cent at least, if not 15 per cent. In return, incometax rates would be indexed and the steps changed to ensure that people on modest incomes do not pay high marginal rates.

A mature debate would conclude that GST exemptions should be removed on things which on first view look like wholesome expenditure on wholesome things: education, health and unprocessed food, but in fact are things wealthy people spend disproportionate amounts of money on and should be taxed on.

The extra revenue could help remove antisocial state taxes on gambling (which the states encourage) and on property conveyances which prevent people moving more easily to the accommodation they want.

Further, a mature debate would expose the immature hypocrisy of the Greens' opposition to indexation of fuel taxes. The Greens have argued long and hard for higher taxes on fossil fuels, but apparently not if a Coalition government is doing it. Damnable hypocrisy.

Bring on the mature and comprehensive tax debate.

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