There is a scene in Macbeth where the appalled usurper watches a dumb-show of all his grisly victims processing through an imagination twisted by guilt, regret and raw fear. Shakespeare gave no lines to the shades of the Thane of Fife, King Duncan or any of the others. There was no need: the power of their appearance and the way it worked on Macbeth's deranged soul was enough to stir the audience.
Last week's Tory party conference had many of the qualities of a 16th-century dumb-show. When Baroness Thatcher emerged from her car to be greeted by the rictus smile riveted to William Hague's face, her mere appearance was enough to dim the house lights and fire up the follow-spot. Looking ever more sharp-featured and hawk-like (in Scotland she is compared to a hoodie - a carrion crow) and growing into the Valkyrie shape of her Gerald Scarfe cartoon, Thatcher's presence electrified the Tory conference and made it news in a way completely beyond the survivors in the shadow cabinet. When she was joined by Lord Tebbit and some of the other bit players in the destruction of the eighties, a collective shiver of recollection shook many in Scotland.
As Thatcher's damage without limitation exercise unfolded, Scotland recoiled, electing fewer and fewer Tory MPs at each general election she called. Tories quickly became an endangered species and when finally none were elected in Scotland in 1997, most of the zoology disappeared from Scottish politics. Perhaps the climactic moment came when Thatcher decided to impose the poll tax first in this country, the place described by Douglas Hurd's Spitting Image puppet as "the northern testing ground".
Throughout her entire period as prime minister, Margaret Thatcher was reviled with particular enthusiasm in Scotland because she was seen as foreign, the sort of hectoring autocrat to be found in other, less democratic and consensual countries. It was very difficult to understand why the southern English continued to elect her. Only the extraordinary prices of houses in London and the Home Counties and Harry Enfield's Loadsamoney character seemed to offer any obvious clues. And while her ability to turn spleen into a political doctrine appealed to the frustrations of some, particularly in the upper echelons of the Scottish business world, her actions in destroying much of what many communities had patiently built since the second world war occasioned first outrage and then paralysed horror north of the border.
Without any overarching organisation, or planning, or ideology, or even an initial awareness that it was beginning to happen, Scotland began to distance itself from Thatcher's England in the 1980s. Scotland became very Scottish, as un-English as it was possible to be. Culture often determines the political weather, and when Scottish writing, both fiction and non-fiction, began to flower alongside an extraordinary tide of popular music, then it was clear that change was under way. The example of Runrig, a rock band from Skye, is instructive. Towards the end of the decade they gained a huge and sometimes worryingly devoted following all over Scotland, and several big outdoor concerts took place which occasionally looked a little like rallies. This was something new and different because many of Runrig's most popular songs were in Gaelic, a language understood by almost no one who listened to them. Instead the fans learnt the words phonetically, read the translations on the album sleeves and chanted along at concerts, most memorably on an August night in 1989 on the Castle Esplanade in Edinburgh. The reason for Runrig's popularity was visceral. It was impossible in popular culture to find anything more un-English than Gaelic songs. Even though 99 per cent of the fans could not utter a word of Gaelic, they certainly got the sense of what was sung and they knew that the English hadn't a clue. And in the eighties, that was important.
When Wee Willie welcomed Thatcher in Blackpool and later, through gritted teeth, lauded her achievements, he should have added something unexpected to the ritual list. More than any opposition politician, she was the political midwife of devolution. Her actions, more than any other single cause, made the Scotland Act a fact.
It is difficult to be grateful, but we should at least acknowledge that out of the wreckage Thatcher made of Britain, something good did emerge. And, as important, she helped to give us the legislative mechanisms to ensure that someone like her at Westminster is never again able to damage our country as much as she did. Should such a fearful apparition rise again in the south, we can now gather on the north bank of the Tweed with powerful constitutional weapons at hand. Thank you, Margaret.