Since the second debate the momentum has shifted firmly to the Yes campaign. This shift has been fuelled by Salmond's emotional message of romanticised Scottishness defined in opposition to Westminster (characterised as a conflation between the Conservative Party, Labour Party (particularly New Labour and beyond) and (southern) England). It is an appealing message to a nation that has felt aggrieved since the industrial decline of the 1980s exasperated anxiety towards England. The memory of the divisions Thatcherism brought remain alive and well in the north (including northern England), despite some attempts by New Labour to redress the inequalities of a neoliberal economy.
Thus the United Kingdom now faces a crisis. It is a crisis that threatens to split Scotland from its closest neighbours as it turns inwards and isolates itself in a moment of long lasting anger. It also has the potential to trigger a constitutional crisis which would see about a re-compartmentalisation of powers not seen since before the Union was established. So, let us assume for the purposes of this short piece that Salmond and the Yes campaign succeed and get the endorsement needed to negotiate for independence. Against the earliest indications and confidences of the Unionists, the Scottish nationalists have managed to gain a mandate for independence. Before proceeding I should stress that the following represents a few speculations which are by no means predictions! Indeed, we simply don't know what would happen if Yes wins and this - like all the other pieces trying to predict it - are mere guesswork that is (in some cases) reasonably well informed. They are, however, still merely guesses.
Firstly, the pressure on David Cameron to resign will become immense. He would be the Prime Minister who lost the Union. Worse still, he will have spent his time appeasing his own party over Europe whilst the UK itself was in peril. It is a rather strange thing for the Conservative and Unionist Party to have done. Also his rhetoric of the 'national interest' will be in tatters since the nations of the Union are no longer together. Given he views the UK as a single entity this will devastate his credibility. So, under such pressure (and more besides) let us assume he does resign, thereby triggering a Conservative party leadership election. Boris Johnson, who is now starting to position himself for a return in 2015, would be the biggest loser. Mostly because the leadership election would take place before he entered the Commons, thereby precluding any further challenge to the new leader (whoever that may be). Indeed, even after Boris enters the Commons the new leader would have a strong case not to resign, given the circumstances of his/her election.
Secondly, some MPs have suggested postponing the general election in order to complete the withdrawal of Scotland from the Union. This is probably worthy of serious thought given any negotiations would not start until after the UK general election anyway. The reason for this is the UK government would not be in a position to do so given it would have to face the risk of removal in 2015, thereby compelling the new government to continue the negotiations on matters that it may wish to renegotiate. Put simply, the Tories may negotiate in a different way to Labour, and that to ensure continuity a UK electoral test should be postponed until the former UK (fUK) is reconstituted. Add to that if there was a 2015 general election then it would bring in Scottish MPs who would subsequently vacate the Commons, possibly precipitating a second general election in 2016 anyway, especially if Miliband wins in 2015 and subsequently loses his majority when Scotland departs.
Thirdly, the negotiations themselves will determine the nature of the relationship that the fUK and Scotland share. In the heat of debate a great deal of emotive rhetoric has been used by both sides, which will need to be forgotten quickly. However the negotiations themselves will be between two newly formed competitors dividing mutually owned resources. No doubt both sides will gain and lose, however the fUK government would have a duty to secure the best resources possible from Scotland, whilst the Scottish government will be using the threat of defaulting on its debts as leverage for Currency Union. It will become a messy divorce which will produce an acrimonious political relationship.
Fourthly, there's the reaction of the markets. Much has been made in the City of the expectation of a No vote. Should a Yes vote be the outcome, then it will send a massive shock through the global stock exchanges, possibly precipitating a crash. The pound will face immense pressure, and confidence in Great Britain (both the fUK and Scotland) will vanish. Banks in Scotland will be looking edgy, and wondering if it's worth taking the leap southwards. Businesses will also be thinking likewise given the inevitable need for tax rises in Scotland to pay for the social packages promised by the Yes campaign and the SNP more broadly.
Finally there is the pragmatic issue of Scottish MPs. Such MPs, especially high profile figures will be looking for another seat if they wish to remain in Westminster. However there is always the option of standing in the Scottish Parliament, but this will detach them entirely from fUK politics. It will be something to consider very carefully.
These are just a few speculations on the effect upon British politics. There is, of course the fallout from NATO at a time when Islamic State is becoming a very serious problem; relations with the EU, the UN, the US, and even the Commonwealth. And of course there's Northern Ireland, alongside the new threat of disgruntled regions in the north of England.
Scottish independence is one of the biggest threats the UK has faced since its inception. As independent nations Scotland and the fUK will become economic competitors, with both sides no longer enjoying the sense of closeness gained through the Union.