Jim Chalmers is clearly struggling. He is presiding over an economy that is simultaneously over-heating, with underlying inflation stuck close to 4 per cent, and stalling, as the June national accounts made clear.

In the annals of economic policy mishaps and misadventures, this is quite an achievement for any government. Chalmers’ response to this unfortunate turn of events, which I describe as full-employment stagflation, has been highly revealing. He has sought to defend his government’s excessive spending, claiming that if it were pared back, the economy would go into recession, a view that ignores that we are experiencing a supply crunch, not a shortfall of demand.

By rejecting public spending restraint, Chalmers is in effect calling for more inflation, higher interest rates or both. The Australian public, who are highly economically literate, are starting to realise this.

Chalmers has also resorted to increasingly desperate attacks on the Reserve Bank – claiming its interest rate policy is ‘smashing’ the economy. As former prime minister John Howard has pointed out, this has only diminished him.

A visitor to Australia would think Chalmers would be at risk of losing his job. While his stocks have no doubt fallen, he has not – at least so far –  been singled out as a ministerial under-performer. And odder still, Angus Taylor, the opposition treasury spokesman, has so far been unable to lay a glove on the Treasurer.

Why? I think the answer, at least in part, is that we no longer expect much from our treasurers. Since Paul Keating and Peter Costello, we have had a string of underwhelming people in this role. Lightweights have taken the place of heavyweights.

Chalmers is not an outlier, but the continuation of an unfortunate trend that started with Wayne Swan and continued with Chris Bowen (Treasurer for Rudd Mark II), Joe Hockey, Scott Morrison (Treasurer for Malcolm Turnbull) and Josh Frydenberg.

It is worth reminding ourselves what distinguishes heavyweight treasurers like Keating and Costello from the others. In my view, it comes down to three things.

First, heavyweight treasurers are guided by a coherent economic framework that shapes everything they say and do.

It is no accident that when making the case for the signature tax reforms they led, Keating and Costello gave us strikingly similar arguments. Both justified them as pro-growth, pro-market changes which would strengthen incentives to work, to save and to invest. And both rejected the ‘fairness’ objection to lower income taxes for higher-earners, putting aspiration, opportunity and social mobility before zero-sum redistribution.

Lightweight treasurers either have no framework at all or one that is hostile to markets and growth.

Second, heavyweight treasurers shape the nation’s economic debate, leaving commentators scrambling to catch up. Keating’s famous boast was true: ‘Every pet shop galah’ did indeed repeat key words from his script.

Lightweight treasurers, in contrast, mistake day-by-day economic commentary for thought leadership. This diminishes rather than elevates them, making them sound like any other economic talking head in the media.

Third, and most importantly, heavyweight treasurers get big things done. They may talk a big game, but they deliver. Lightweight treasurers, by contrast, either accomplish nothing, botch reforms they have carriage of, or satisfy themselves with rats-and-mice policy announcements.

Can you think of a single, economy-wide, pro-market reform a post-Costello treasurer has successfully implemented? Nor can I. Swan’s panicked response to the global financial crisis does not count; and nor does Frydenberg’s jettisoning of liberal principles during the pandemic.

I think it’s pretty obvious what type of treasurer Jim Chalmers is. Rather than internalise the philosophical framework that guided Keating and Costello, he derides it as neo-liberal or economic rationalist. While he subscribes to a form of anti-economic economics, in truth, Chalmers has no coherent economic view.

In addition to his lack of understanding the causes of inflation, Chalmers thinks that stunting the supply side of the economy (by making labour and electricity more expensive) will stimulate growth. And he has invented a notion of productivity that is entirely his own, including bizarre and irrelevant references to net zero and the caring economy.

Nor does Chalmers rate highly on effective communication – given his penchant for word salads and alliteration –  or reform achievements.

Yes, he has delivered two budget surpluses, but these were the result of revenue windfalls not of spending restraint on his part, with bracket creep (a regressive tax on lower-income earners) playing a large role. Those surpluses will soon be replaced by deficits as far as the eye can see. On structural policy, Chalmers has been a bystander as Tony Burke and Chris Bowen have wreaked havoc in their portfolios (in Burke’s case, before he moved to Home Affairs).

Strong treasurers matter. We tend to analyse inflation in dry economic terms, but at its heart it is a result of policy and political failure.

From central banks who, having usually caused it in the first place, want to soft-pedal their response to it. And from treasurers who want to fund every worthy cause, losing sight of the need for fiscal prudence. When Chalmers speaks emotively about not wanting to ‘smash’ the economy (despite federal spending growing at a rapid clip) what he is really saying is that he can’t stomach making necessary but unpopular decisions.

Treasurers should be made of sterner stuff, regardless of their politics. Keating once said that leaders must have two qualities: imagination and courage. I think this applies particularly to treasurers. Their imagination must be grounded in hard fiscal and economic realities, informed by sound economic thinking, not a Walter Mitty-like fantasy that this discipline can be reinvented.

And courage requires a willingness to say no to the constellation of spending ministers, lobby groups and vested interests looking to bleed taxpayers dry; the boldness to set out painful economic choices for the community; and yes, a preparedness to wage the good fight, even against your own party’s base, to allow market forces freer play.

In the irony of ironies, Jim Chalmers, who completed a political dissertation on Keating, conspicuously lacks the very qualities his subject extolled. But he is not much worse than his recent predecessors, all of whom shrank rather than grew in the job.