During the years of the Thatcher governments the Scottish economy was transformed at a faster and more radical pace than during the classic phases of the Industrial Revolution.

That great watershed in the nation's history took several generations in the late eighteenth and early nineteenth centuries; the revolutionary changes of the 1980s a few years.

In 1979 one in three Scots was in industrial employment. Five years later the figure had fallen below one in four. Manufacturing capacity dropped throughout the UK but the decline in Scotland amounted to a collapse, with a loss of 30% in the 10 years from 1977 to 1987. The traditional staples of the economy crumbled with alarming speed. By 1997 deep-mining was confined to one complex at Longannet. Only a handful of shipyards survived on the Clyde. The disappearance of technical capacity was so acute that when the Clyde-built QE2 was re-engined with diesels in 1987 the work was carried out in Germany. The last cargo of raw jute for the Dundee mills was landed in 1998. The giant steel strip mill at Ravenscraig finally closed in 1993.

The hurricane also swept away many of the new industries of recent foundation that were seen as Scotland's hope for a prosperous economic future: the car plants at Linwood and Bathgate, aluminium smelting, agricultural machinery making, tyre manufacture and many more. By the end of the 20th century the nation with a global reputation for making things for world markets had a lower proportion of the working population engaged in industry than the average for the UK as a whole. In less than a decade an economic system in which the majority of the Scottish people had been employed since the 1850s came to an abrupt end.

Inevitably, the social costs for families and communities were huge. In 1985 unemployment peaked at 16%, but that did not include the numbers of young people on youth work schemes and the many individuals transferred to invalidity benefit.

The rate of unemployment in Scotland was between one-quarter and one-third higher than in the UK as a whole – and this in a country accustomed to the full employment policies of successive governments since the 1950s.

More subtle forces than factory closures were also having an impact. This was also the time of "downsizing" and "streamlining" as productivity levels were boosted. The result was to spread insecurities and anxieties even among those who were fortunate enough still to be in a job.

This economic maelstrom was blamed by many not on global economic forces but on an uncaring government committed to the pursuit of ideologies that had unleashed a social catastrophe and so destroyed the post-war political consensus on support for employment and the welfare state. A new word, Thatcherism, entered the lexicon. It came to mean monetary control, liberalisation of free markets, reduction in trade union power and a drive to inspire self-help in a country thought for too long wedded to state dependency and welfare support.

What raised the hackles of the Scots was that these policies were judged alien, implemented by a government they resoundingly rejected in successive elections and led by a prime minister who in voice and personality seemed to stand for a certain type of Englishness which many, to say the least, found distinctly unappealing. These perceptions had long-run historical consequences. They destroyed the Conservative Party as a credible political force in Scotland and inspired a much greater commitment to the cause of devolution. Margaret Thatcher, the arch-Unionist, can indeed claim to be the mother of the new Scottish Parliament.

Yet, from today's perspective, was the blame attached to the Thatcher governments fair and realistic? How far indeed was the social and economic revolution of the 1980s driven by ineluctable economic and intellectual forces that affected all industrial regions of the developed world, whether in the old manufacturing heartlands of Europe or the rust-belt states of the US? Did the Thatcher governments simply deliver the coup de grace to an economic system already dying and with no chance of survival in the rapidly changing world of late 20th century capitalism?

There is some evidence to support such an interpretation.

First, Scotland in the 1970s had an ossified and archaic industrial structure which had hardly changed since late Victorian times. Steel, shipbuilding and coal in particular suffered such consecutive losses in the 1960s and 1970s that their survival could not have been sustained without massive state support.

Secondly, the destructive forces that ended their existence were indeed global in scale, affecting Scotland in the same way as other regions and triggered especially by the steep increase in oil prices in the early-1980s that hastened a collapse in world demand for manufactured products.

Thirdly, not all regions of Scotland were badly affected. The trauma suffered by those districts of the west central lowlands in the storm of de-industrialisation was not replicated in Edinburgh and Aberdeen and their hinterlands.

Fourthly, the worst years were already over by the late-1980s. The costs had been high but, by that period, Scottish GDP was rising faster than in the industrial regions of England and Wales, and had also improved relative to other mature economies such as Belgium, Denmark, the Netherlands and Sweden. Indeed, the dramatic reduction in earlier loss-making capacity, coupled with expansion in banking, finance and electronics, pushed Scottish GDP per head to the UK average in 1995. A new and more diverse economic structure had emerged better suited to the conditions of the new millennium.

Nonetheless, it is difficult to ignore the fact that, by acting so swiftly and radically on an already enfeebled economy, the Thatcher governments did immense damage to the social fabric of Scotland and to Anglo-Scottish relations.

Their obsessive and virtually exclusive concentration on squeezing inflation out of the system meant that bank rate was held at no less than 14% or more for 21 months from June 1979 and then again in the winter of 1981/82. These policies imposed even greater pressure on industries already rapidly succumbing to the decline in global markets. A more evolutionary approach might have led to the same beneficial consequences in the long-term but spared the country some at least of the resulting pain and anxiety.

Since the late 18th century the stability of the Union had depended on a partnership of interest between Westminster and Scotland. Mrs Thatcher disturbed that age-old relationship by imposing policies thought by many Scots to be not only unacceptable but even anti-Scottish in nature. By doing so, she and her colleagues destabilised a Union of which she and they were such ardent supporters. The consequences for the future of the UK as a whole are still being worked out.