This week has been quite the advert for fiscal autonomy

His apparent logic was that Sir Keir’s policy of gradual withdrawal from drilling for hydrocarbons in the North Sea is a green light for Just Stop Oil’s behaviour. It’s nonsense, of course. Sir Keir’s energy policy, in as much as it is clear, is misguided on the link between the profits of the hydrocarbon industry and the funding of renewable infrastructure, but it is clearly not the same as the Just Stop Oil policy of torpedoing the oil rigs today. Indeed, Sir Keir has gone out of his way to lambast the intemperate protest group.

So Mr Shapps’ actual logic was that Sir Keir is the Prime Minister in waiting and he needs to do anything he can to pin him to an unpopular cause, irrespective of the accuracy.

He’s not the only one who’s at it. Also on Wednesday, the SNP sent the Westminster media coffee mugs emblazoned with "Controls on family sizes" and "The Labour Party has a new range of mugs in production. They’re made in China - just like Sir Keir Starmer’s latest policy".

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The intention was to pile the pressure on Sir Keir about his decision not to reverse the policy of limiting taxpayer-funded child benefit payments to two children, implying that it has a similarity to China’s one-child policy, which led to gender-selective abortion, abandonment of baby girls and, in some cases, infanticide.

If we put aside the fact that the one-child policy no longer exists, and the fact that relations with China are delicate as they act as a strategic check on Vladimir Putin, comparing a democratic country’s policy of placing a limit on a state payment to a Communist country’s policy of criminalising childbirth is immature, at best, and at worst rather dangerous. And all in the name of arresting the (still small) movement of votes from the SNP to Labour.

I get how these things come about. A bunch of young guys (they are usually young and they are usually guys) come up with a clever idea for how to get a lot of retweets and maybe even squeak some mainstream media from the coverage. I’ve been one of those guys in the past.

For the rest of us, though, these two episodes were moments of deep cringe and eye-rolling.

The furore over the two-child cap this week has made me think, once again, about a concept which has dropped out of political discussion over the last couple of years. It’s what we used to call fiscal autonomy - the concept that each layer of government should raise what it spends.

It is, of course, a breeze for the SNP to rail against difficult spending decisions, because it has little responsibility for raising the money which pays for them. This is not its fault - the blame lies at the door of the Barnett Formula, the system which allocates a budget to the Scottish Government, which it then spends.

Ironically, for a construct which is designed to promote unionism by giving Scotland far more money to spend than we contribute in taxation, the Barnett Formula in fact hands the SNP the power to spend lots of money, to advocate for spending of even more, and indeed even to criticise the Westminster Government for underfunding Scotland.

The entire political discourse would be forced to change if we required all levels of government (and I would include local authorities in this) to raise the money they spend. A Scottish Government responsible for raising the money to pay for a welfare system is a different beast indeed from the campaigning Scottish Government of this week.

Sir Keir is dealing with an entirely different decision matrix. The UK has, all at once, emaciated growth, a budget deficit, eye-watering debt and a proportionately reducing taxpayer base. Layered on top of that is Labour’s political need to persuade the centrist majority in the UK that a party which was recently led by a Marxist, is able to run an economy.

Scrapping the two-child policy, in isolation, would not cost much. And, indeed, there are persuasive arguments that the policy is wrong-headed in a country which continues to need population growth. But the policy is part of a complicated myriad of welfare payments which, in reality, amount to a fairly generous benefits system by international standards, and one which swallows a vast proportion of government spending, often with little discernible return.

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Whilst not immediately obvious, fiscal autonomy would in fact be a blessing in disguise for the SNP. The 2014 referendum campaign was lost, in the main, because "middle Scotland" simply didn’t buy the economic case for independence. Until the SNP can prove that it understands economies and has a credible plan to run a successful one, then it has little or no chance of achieving its raison d’etre.

The Scottish Government’s dalliances into matters economic tend to revolve around increasing the taxes over which it has power, in the name of progressiveness but most likely reducing the potential tax base and overall tax take, and spending any available money on unreformed public services.

Successful, small countries are not made of this, and voters know it. That’s why they chose the devil they knew in 2014, and, as polls show, would most likely do so again if given the choice.

On the other side of the political coin, fiscal autonomy would administer a shot in the arm to whichever new party replaces the Conservatives as the primary party of Scotland’s centre-right. There is absolutely no future for any centre-right party in a country where government is merely a spending competition - the centre-right can never win that.

Fiscal autonomy would be a win-win, ending childish political arguments and simultaneously promoting better government. As Abraham Lincoln said, you cannot escape the responsibility of tomorrow by evading it today.