Throughout last night, a long, rather anti-climactic night, the 1992 general election kept going through my mind.

In the weeks leading up to that UK-wide electoral contest, many assumed the SNP were on the cusp of a breakthrough: the Scottish Sun had backed independence (unlike this time) and one poll had even shown a majority for Scotland becoming free, as Alex Neil put it, by '93.

Yet it was not to be. Although the SNP vote increased significantly it won only three seats in the House of Commons. Of course this morning's result wasn't anywhere near as bad, yet the gap between expectations, especially in the final heady days of the campaign, and the final result will be familiar to Nationalists of a certain vintage.

The spirit of 1992 also played out in other respects. The pattern of Yes votes, particularly on the West Coast, was a painful reminder that the Labour Party is in serious trouble.

Although the exact proportion of its voters going for Yes is as yet unclear, it is likely to have been high, reflecting disillusion with a formerly mighty movement that is likely to impact on future electoral contests.

Neil Kinnock got the message 22 years ago, but will Labour's current leadership? If anyone emerges with an enhanced reputation from the referendum battle it is Gordon Brown, a Labour politician of another era, rather than the current leader Ed Miliband.

Beyond having secured a No vote - a not insignificant achievement for the UK's major Unionist party - there will be many humbling lessons to be learned.

The same goes for the Conservatives, the oldest and yet at the same time weakest party of the Union. As in 1992, the Coalition government ought to view the referendum result as a reprieve rather than a victory. The Union, as the constitutional lawyer Adam Tomkins recently observed, can only be saved once; in future, Scottish voters will need positive reasons to support the status quo rather than just a fear of the alternative.

But beyond defeat, the National Movement - as in 1992 - can take comfort from the headline figures. By any measurement, 45% is a good result for the SNP and broader pro-independence campaign. For decades, independence support has hovered around the 33% mark, now it is within touching distance of a majority.

Next time round, and there will be a next time, there could easily emerge a 55/45 split in its favour, rather than No.

The Prime Minister is well aware of this, which is why his response this morning was surprisingly far-reaching. Not only does he intend to stick to Gordon Brown's timetable for more powers in Scotland, but at the same time he plans a UK-wide process which will attempt, perhaps quixotically, to deal with the elephant in the room - otherwise known as England.

There is much talk, as in all periods of constitutional flux, of federalism, but in truth what David Cameron intends still falls far short of that Liberal Democrat dream.

Yet by finally recognising England as a Home Nation and embarking upon a holistic reform process, the UK becomes ever more quasi-federal in nature. Taking this to its logical conclusion ought only to be a matter of time. That is, of course, if Unionists are serious about winning not just the battle but also the broader constitutional war.

In retrospect the 1992 general election represented a paradigm shift in British politics, when one political ascendency (the Conservatives) began to give way to another (New Labour), and 2014 has a similar feel.

Whether the Unionist parties realise that and, more importantly, respond adequately, will be revealed in the months ahead.