Unravelling budgets have become something of a tradition. While “day one” of a government’s spending plans might go smoothly enough, “day two” brings to light the small print, while “day three” is dominated with news of a major blunder.

Last week’s Scottish Budget didn’t quite go the way of several “omnishambles” statements at Westminster, but there was still a spate of stories in the days that followed: the Tories claimed pensioners would be hit, while Labour pointed out that those earning between £43,000-£58,000 would actually pay less income tax next year.

In this respect, Scotland is becoming more like a “normal” country – to borrow Nationalist terminology – and, dare I say it, more like the United Kingdom. The Scottish Government only being responsible for spending money rather than raising it has long stymied political culture north of the Border and that, at long last, is beginning to shift.

It’s also no exaggeration to say that what Finance Secretary Derek Mackay set out on Thursday afternoon will set the terms of political debate for the next three and a half years, although it’s likely to have positives and negatives for the SNP, Conservatives and Labour. This, too, is a good thing.

For the governing party, which has long flaunted its rather tenuous “progressive” credentials, it can now argue with a modest degree of justification that it’s finally made good on years of rhetoric. Sure, the Budget didn’t raise very much additional revenue, but it’s enough for the SNP to claim it’s “mitigating” Tory austerity. Nationalist “radicals” are generally comfortable mitigating things.

The creation, in effect, of a new income tax system for Scotland also allows the First Minister to break ideologically with her more centre-right predecessor who, following the 1999 “Penny for Scotland” election campaign, subscribed to the very British orthodoxy that tax rises were electoral suicide. And, usefully, the next Holyrood election is more than three years away, time for voters to get used to the new fiscal reality.

On the other hand, I suspect debates about Scotland’s (currently) notional fiscal deficit will increasingly be framed in terms of the new income tax bands and associated increases. Hitherto, talk of £15 billion “black holes” has all been well and good, but hereafter expect the Conservatives (and others) to translate that into eye-wateringly large projected increases to all five income tax bands.

Indeed, the Scottish Tories could barely contain themselves last week, content that Christmas had come early with a traditionally Conservative stick with which to beat the SNP between now and the next election. That said, to my ears the “Nat Tax” line didn’t really land – perhaps they should have stuck with Michael Forsyth’s 1995 “Tartan Tax” jibe.

At the same time, there is an irony in the Conservatives attacking the Scottish Government for exercising new fiscal powers that exist thanks to legislation passed by a UK Tory government. At a Christmas drinks reception a few hours after the Budget, Scottish Secretary David Mundell half-jokingly accepted responsibility for the forthcoming tax rises.

But, more seriously, if the Tory line until 2021 is going to be that they intend to reverse last week’s tax changes, then they’ll have to identify the public spending cuts necessary to bring Scotland back into line with the rest of the UK. Conscious of this, the party recently identified £210 million in “efficiency savings”, but that is unconvincing.

There’s also an irony in the SNP suddenly learning to stop worrying and love tax rises. Ever since it became clear Westminster was prepared to devolve major fiscal powers to Edinburgh, some Nationalists spoke of a “Unionist trap”, a cynical attempt to push the Scottish Government into making tax rises and therefore lose votes in future elections.

There was always some truth in that but, in any case, the SNP has now walked into that trap, although that probably has more to do with its need to take on Labour rather than worrying about Tory tactics. On that point, Scottish Labour leader Richard Leonard’s response to the Budget last week was pretty weak. In his Holyrood speech and, later, an article for Common Space, he denigrated Sturgeon and Mackay for revealing their “timidity” rather than showing “courage”.

But at no point did Leonard say what he would have done had he been in charge. Indeed, Derek Mackay’s George Osborne-like laying of political traps means Labour will, at some point between now and 2021, either have to set out even more “radical” tax increases or say nothing and look rather foolish. Having a full-time finance spokesperson would help, but then Scottish Labour still doesn’t have a new front bench.

Beyond Holyrood, the Budget was greeted with the usual bleating from business organisations warning of calamity as a result of a penny on the higher and additional rates. If any of these outfits ever advocated tax increases – and one suspects they would not even were the Scottish economy booming – then that might carry some weight. In spite of all the hyperbole, the SNP is hardly taxing people until the pips squeak.

Entertainingly, Alex Salmond’s favourite economist Arthur Laffer even warned from across the Atlantic that the Budget would “drive businesses and skilled workers” out of Scotland. But while the Finance Secretary famously admitted to not knowing what the “Laffer Curve” was, his Budget actually abided by its principle that there are diminishing returns beyond a certain “optimal” tax rate.

As the Finance Secretary pointed out last week, the Scottish Fiscal Commission had done the modelling and he had therefore set income tax policy at levels “the analysis says will generate additional revenue”. Art Laffer can rest easy, as can all those who advocated a Scottish Parliament with financial “teeth”. With the SNP’s modestly creative plans, devolution has finally begun to bite the bullet of fiscal responsibility.