Where to start with Michael Marra’s comment about the Scottish Government’s Budget being “based on the economically and fiscally illiterate assumption that income tax can be used to plug the hole left by the SNP’s failure to grow the economy”.

It is, of course, a most politically convenient assertion from MSP Mr Marra, Scottish Labour’s party spokesperson on finance.

However, it does not stand up to scrutiny.

Mr Marra should know, surely, that the fortunes of the economy in Scotland are inextricably linked to those of the UK as a whole.

The Scottish Government does not in reality have major economic levers under the current set-up.

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Of course, it has some devolved economic powers and has done a good job with some of those, as can be seen with Scotland’s success in attracting inward investment. There was a sensible acceleration of infrastructure spending from Holyrood in the wake of the global financial crisis, although the capacity to boost such expenditure unilaterally is severely constrained by the devolved funding arrangements.

In short, the Scottish Government’s economic powers are small potatoes indeed. And they most certainly pale into insignificance relative to the wrecking ball the Conservative Government has taken to the UK economy.

Mr Marra, as someone who would presumably in many other circumstances highlight the huge degree to which Scotland is intertwined with the rest of the UK, should realise that this wrecking ball has hammered the economy north of the Border as well as every other part of Britain.

You would think Mr Marra and his Labour colleagues in Scotland might want to highlight the great damage caused by the Conservatives.

However, most of the time, they seem entirely wrapped up in pointing their fingers at the SNP and its junior partner, the Scottish Greens.

You could with some justification take the broad view that Scottish growth should be expected, under current arrangements, to amount to the expansion in the UK as a whole minus the drag from Scotland’s particularly acute demographic situation. Scotland faces particular challenges when it comes to the size of its working-age population, and notably the outlook for this. The population is ageing throughout the UK, but Scotland faces particular difficulties.

Of course, free movement of people between the UK and European Economic Area countries was a crucial means by which Scotland could tackle or at least mitigate this challenge.

This great benefit was removed by the Tories’ hard Brexit. And Labour, unfortunately, has made it clear it will not bring it back, having ruled out the UK rejoining the single market if it wins power.

And this red line for Labour means that the blow to Scotland’s exporters from Conservative policy, with the hard Brexit resulting in the loss of frictionless trade between the UK and EEA countries, will also not be reversed or mitigated in any way.

To be fair to Mr Marra and Labour, they did not cause the Brexit damage.

However, they have made it clear they will not address it, and that is lamentable.

Obviously, for political reasons in Scotland, you can see why Labour wants to point the finger at the SNP and accuse it of failure on the economic front.

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This, however, seems somewhat disingenuous from Labour. Surely it must know the blame for what has been visited upon Scotland lies at Westminster.

It was the Tories who delivered the hard Brexit. Then again, with Labour making a big noise about not rejoining the single market, we can perhaps see why Mr Marra would not want to shout too much about that.

In fact, he and his Labour colleagues might not want to talk about Brexit too much at all to the electorate north of the Border, given the big vote in Scotland to remain in the European Union.

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The UK’s economic output has fallen short of that of similar countries by about 5% since the 2016 Brexit referendum, economists at investment bank Goldman Sachs observed last month.

Another dreadful thing delivered by the Conservatives (from 2010 onwards) which has laid Scotland low is grim austerity, with savage cuts to welfare and public sector pay freezes and caps.

You could be relatively “economically illiterate”, to use one of Mr Marra’s own phrases, and still realise that such policies have taken many billions of pounds out of people’s pockets and thus weighed very heavily on aggregate demand and growth over the years.

Surely Mr Marra must be aware of this effect? Austerity has hampered the whole of the UK, although Scotland looks to have been one of the worst-affected areas, given the make-up of this savage programme.

The International Monetary Fund forecasts the UK economy will this year record the second-weakest growth among the Group of Seven leading industrialised nations.

The UK is expected by the IMF to expand by just 0.6% in 2024, marginally ahead of the 0.5% forecast for Germany.

France is forecast by the IMF to grow by 1% this year. The US is projected by the IMF to expand by 2.1% in 2024.

There is, of course, plenty of scope for valid debate over how much people should be taxed and how money should be spent in the context of the quite limited devolved fiscal powers of the Scottish Government.

In Scotland, higher earners pay more income tax. However, you can see instantly some benefits in terms of spending, including free university tuition for people living in Scotland and the Scottish child payment.

In recent times, it has become increasingly frustrating to hear those who should know better paint a picture that the Scottish Government has some kind of huge economic and fiscal powers.

And it is, frankly, utterly demoralising to hear Mr Marra’s assessment of Scotland’s finances and economy.