Barnaby Joyce is the gift that keeps on giving. He is possibly the greatest – genuine – ever gift to One Nation. But now he’s a gift – of a different kind – to the Coalition.

I reckon I’ve banked enough Barnaby brownie points over the years to have this crack.

For years I’ve defended Barnaby to my city friends, who have always dismissed him as the Coalition’s village idiot. As I have said many times and for many moons, if I were the Member for New England, I’d be banging on about the things he bangs on about. Besides, we share some of the same obsessions: the scourge of large-scale renewables and native vegetation regulation – both at a point where technocratic blindness to real-world problems has created some terrible unintended consequences in far-flung rural communities. But I digress.

Mind you, Barnaby has never been the bloke sharpening the pencil out the back. He’s all front of house. He’s the bloke selling the steak, not costing the menu.

Tony Abbott understood Barnaby better than anyone. He rated Barnaby as one of our greatest retail politicians. But when it came to carrying the Coalition’s economic credentials, within a few short months of giving Barnaby the opposition finance brief, even Abbott decided Barnaby’s – er – ‘best talents’ lay elsewhere.

Full disclosure. It takes an innumerate to know one. I spent my career avoiding commercial law like the plague. I’m not the person you’d ask to build a budget model or add anything up.

But I do know this. If you’re asking Australians to hand you the keys to the Treasury, sooner or later you have to do the maths.

Which brings me to this week.

Elsewhere I’ve argued that insurgent parties eventually run out of performance and run headlong into scrutiny. This is happening in the United Kingdom right now, and Barnaby clearly gets this. As One Nation’s Treasury spokesman, Barnaby recently announced that he’s ‘back to accountancy and being an economist at the moment’. Good stuff.

That was before Angus himself did Barnaby’s accountancy and economics for him. Angus called out the world of economic pain were headed for if you just add One Nation’s four most expensive policies. Just for starters – sticking with steaks, the prawn cocktail entrée if you like – it is very serious: 3 per cent higher rates, massive additional debt, and a likely sovereign debt crisis.

Pauline scolded Angus for being a naughty boy – and unleashed her digital armies. But Barnaby responded initially with characteristic honesty; an acknowledgement that One Nation had work to do on economic credentials. He then suggested that to manage inflation, if One Nation held the Treasury benches they’d ask the Reserve Bank to help them with spending cuts. This was as nutty a response to an economic issue as I have ever heard. We likely won’t hear about it again.

But it got better. Laura Jayes pressed Barnaby about Angus’s criticism of One Nation’s economic policies.

Barnaby’s response?

What would Angus know? And then Angus should ‘show us the numbers’…

I’ve been giggling, just tickled pink, ever since.

No, Barnaby.

These are your numbers. Or at least they should be. You need to show us your numbers.

Barnaby ‘now back to accountancy and economics’ Joyce, is telling Australians that it is for the Liberal Party to ‘show us’ One Nation’s numbers.

You couldn’t script it. And only Barnaby could get away with it. No journalist blinked.

Now I am sure that Angus is showing the numbers to anyone who asks – journalists, colleagues, strangers in airports, for that matter. He’d show you if you asked nicely, Barnaby. But Barnaby, you don’t even need the Parliamentary Budget Office to do this for you for. You can ask ChatGPT. It does accountancy and economics very well.

Barnaby’s line gave the game away.

Barnaby has no intention of doing the numbers because he knows they are terrifying. But the response might have been less avoidance and more muscle memory. Barnaby still assumes someone else will do his homework. That’s how Westminster government works, of course. If you can’t do the numbers, there’s someone else in the team who can and will.

But not Barnaby, and not One Nation.

Conservatives rightly talk about preserving institutions. That requires stewardship. That requires a conservative government to rebuild and then hand on a stronger country than the one we inherited.

But stewardship begins with doing the maths. It most certainly does not end with it. There are many important matters for conservatives to attend to right now. The small matter of saving Western Civilisation for starters. But it begins with a budget. That is why the Treasury role is the second most senior to the Prime Minister in any Westminster system.

‘Show us the numbers’ from Barnaby wasn’t just a funny line. It was an abdication. One Nation’s Treasury spokesman isn’t producing any numbers. It seems unlikely he or One Nation ever will.