THOSE with long memories will recall that the Queen’s speech marking the opening of the Scottish Parliament in 1999 was unmistakably optimistic.

Addressing MSPs in the Church of Scotland’s Assembly Hall - at that point the Parliament’s makeshift home - the monarch captured the upbeat mood of the time.

It was a “historic day”, she said, a “moment rare in the life of the nation” when Scotland stepped “across the threshold of a new constitutional age”. Over centuries “the British” had weighed “continuity and change” in the forging of “new political structures”. Devolution amounted to a “new era of Government”.

1999 seems like a century ago. Back then, Labour and the Liberal Democrats commanded a majority of MSPs and formed the Scottish Executive. The SNP returned 35 MSPs in the first election, but they were a protest party at that stage rather than an alternative Government.

At Westminster, under Tony Blair’s leadership, Labour had a majority of over 170. The Tories were, as they are now, split on Europe, but their obsession with the EU was played out on the Opposition benches. There was also a serious discussion underway about the UK joining the Euro.

However, the Queen’s message that day was a mix of hope and realism. She informed MSPs that they carried a “heavy burden of responsibility” in meeting the challenges set by the new Parliament. They were obliged, she said, to set “lasting standards of vision and purpose” for future generations.

The first eight years of devolution stuck to a workmanlike script. The Labour-led coalition took a managerial approach to devolution by delivering piecemeal changes which were characterised by caution. The Dewar and McConnell years were a melange of rows, gains and under-delivery.

The Queen’s address yesterday struck a different tone to her words twenty years earlier. It was not a speech in which she lathered congratulations on our politicians. Two decades on, she said, Holyrood was an “important” forum and a home for “passionate debate”. MSPs, she added, “strive” to be responsive to voters. Her sober summary was half the length of her 1999 delivery.

Two forms of nationalism account for the changed political mood. The rise of the SNP - through their victory in 2007 and landslide win four years later - has been the dominant story of the devolution era. Scottish politics used to be about the distribution of wealth and opportunity, but Alex Salmond changed the dial so that voting behaviour became inextricably linked to the constitution. Paradoxically, the Yes defeat in the 2014 referendum bolstered the SNP.

The 55-45 result seemed a comfortable victory for the No side, but the Queen realised how close Scotland came to leaving the UK. This was inadvertently revealed by David Cameron during a conversation with former New York mayor Michael Bloomberg:

“The definition of relief is being the prime minister of the United Kingdom and ringing the Queen and saying: ‘It’s alright, it’s OK’. That was something. She purred down the line.”

A resurgence in English nationalism, manifested through Brexit, has also turned politics on its head. It has created a situation where most Conservatives believe delivering Brexit is more important than Scotland remaining in the UK, a set of priorities that would have been unthinkable twenty years ago. The resistible rise of Boris Johnson, a human stink bomb, is another symptom of this phenomenon.

These are dark days for any Unionist. Johnson’s anticipated victory in the Tory leadership contest against Jeremy Hunt, coupled with the possibility of a no deal Brexit, are a potential nightmare for the 312 year Union. Nearly 50% of Scots now back independence, while a sizeable portion of English voters do not care about the UK.

As the world’s longest-reigning monarch, the Queen has outlived passing fads and trends. Her public service has overlapped with eleven US presidents and thirteen Prime Ministers, including Harry Truman and Winston Churchill. She has listened to, and no doubt humoured, fashionable talk of revolution and radical change.

At 93, she may be confident that the United Kingdom will not break up while she is alive. But what about her successors? In twenty years, what will Scotland look like when King Charles (or his son) is invited to address Holyrood? Will they even be asked? Scotland could be independent, a republic, or both. Our turbulent present may herald a thunderous future.