It may be more than 23 years since she last held office but the late Baroness Thatcher has now been drawn into the battle over Scottish independence – by the Nationalists.

In fact, the real surprise is not that Alex Salmond has decided to invoke the legacy of Thatcher in his crusade to break up Britain, but that he has taken so long to do so. Lady Thatcher has long been seen by the SNP as the perfect recruiting tool for Scottish nationalism. They have always liked to portray her as a public sector-slashing, industry-destroying, remote, anti-Scottish Tory.

So when papers emerged last week under the 30-year rule showing that Lady Thatcher had tried to cut a swathe through the Scottish budget in 1984, the Nationalists seized on it. A spokesman for Mr Salmond described the revelations in the papers as ‘astonishing’, not just because Lady Thatcher tried to cut a massive amount from the Scottish budget but that this was concealed from Scottish voters.

Today the Scottish Government has followed this up with a first-person piece by Mr Salmond in the Scotland on Sunday newspaper, which was published this morning. This not only builds on the SNP’s message from ‘Thatcher papers’ published last week but shows how the Nationalists intend to use Lady Thatcher’s legacy through the campaign.

It also demonstrates clearly how Mr Salmond intends to try to draw David Cameron into the same arc of fire, painting him, not just as the heir to Thatcher, but as someone who is planning to do exactly what his predecessor tried – and failed – to do. This is what Mr Salmond says in Scotland on Sunday:

‘Today, I have written to David Cameron, following last week’s revelations that the Tories hatched a secret plan to cut Scotland’s budget in the 1980s. This confirmed what most Scots already knew – the Tories can’t be trusted with Scotland’s finances.

‘If there is a No vote in September, this is what they would do. Their target is to cut Scotland’s money by £4 billion. Cameron’s 18-month guarantee of just a few weeks ago is blown apart by these revelations. The evidence of the past should be taken as a warning for the future.’

This is canny yet it is also more than slightly disingenuous. Mr Salmond’s argument seems to be this – a Tory Prime Minister wanted to cut Scotland’s budget 30 years ago so it stands to reason that a Tory Prime Minister today will do exactly the same thing. This may not stand up to any proper scrutiny as a rational argument but it is clearly one that Mr Salmond believes will win him votes.

It suits the Nationalists to invoke the ghost of Thatcher and her legacy because they believe she remains the hate figure in Scotland that she once was. But is that really true?

Among political diehards and those who fought all those battles back in the 1980s, Lady Thatcher is still hated – we saw that in the way that some people on the fringes of politics reacted in such a tasteless and sour way to her death last year. But Mr Salmond has already extended the franchise down to include 16 and 17 year olds for the referendum. This means that there is an increasing proportion of the electorate with no personal recollection of Lady Thatcher as Prime Minister. Really, voters have to be at least 40 years old to really remember what the Thatcher years were like in Scotland.

What this Thatcher tactic does is confirm the increasing prevalent view that Mr Salmond’s strategy for the referendum is now relying on one simple premise – if you don’t like the Tories, vote for independence.

The Thatcher factor is just an extension of that one argument but whether Lady Thatcher still has the power to mobilise Scottish opinion in the way she once did remains open to question.

There is one other interesting aspect of the Government papers on Scotland which emerged last week which has had not quite so much attention from the Nationalists, though. This was the revelation that the Scottish Secretary at the time, Sir George Younger, not only fought the calls for Scotland’s budget to be slashed, but he was largely successful in achieving that.

The papers show that Sir George stood up to his then Prime Minister, argued against the demands that he cut a chunk out of the Scottish budget and succeeded in protecting it, almost in its entirety.

Here was a Conservative Secretary of State, standing up for Scotland and protecting its budget – now that’s not something that Mr Salmond is ever likely to crow about.