Sometimes, things that you expect still take you completely by surprise. The tangible electricity in the air as applause erupted  around me at the Scottish National Party (SNP) Conference with First Minister Alex Salmond’s call for the Trident replacement to be scrapped, was one of them.

Such a response is to be expected after all from a SNP audience, as the party has long called for the renewal to Trident, the UK’s nuclear deterrent system based in submarines on Scotland’s River Clyde to be scrapped. Mr Salmond’s call for “Not a single nuclear weapon on the river Clyde” was therefore not exactly a hard sell in Inverness on Saturday (Oct 19).

But, occasionally things feel inexplicably different and the passion and sense of determination that reverberated around the auditorium to the calls for no trident seemed to reflect a government and a nation united, brimming with confidence, self-belief and determination. Whether buoyed by the recent defiance of Justice Minister Kenny MacAskill’s decision to free dying Lockerbie bomber Mr. Al Megrahi and send him home to Libya in the face of opposition from Westminster and Washington, something had changed.

With such opposition, how far can the boundaries of devolution be pushed? Even though devolution is supposed to retain within its framework a unified defence and foreign policy remit for the UK, if Scotland opposes, can other parts of the UK expect the Scots to house Trident’s replacement?

No government in Westminster can surely have forgotten the last time a policy was forced on Scotland without its consent. Mrs Thatcher’s decision to levy the poll tax on Scotland caused unprecedented civil unrest and this was at a time when Scotland was controlled centrally from London. A defiant, devolved Holyrood administration (with the SNP likely to win the next Scottish election as well) would surely be an insurmountable object to a similarly unpopular policy.

And it is not just the SNP government in Scotland that is opposed to Trident’s replacement. The majority of Scottish people oppose the replacement as well. A 2007 ICM poll commissioned by the CND, asked respondents “whether they would support UK government plans to continue to have nuclear weapons in Scotland for up to 50 years”. 64% of respondents opposed nuclear weapons, with only 30% supporting nuclear weapons. A more recent UK wide ComRes poll for the Independent newspaper in September showed similar findings, with a margin of 58% to 35% of respondents believing that the £25bn renewal of the Trident programme should be abandoned because of the state of the public finances.

Two things are very apparent from the current situation over Trident. Specifically that for those who support Trident’s replacement as a viable nuclear deterrent or diplomatic tool, the question of where to put Trident’s replacement is arguably as important as when or how it is replaced. For those who do not support Trident’s replacement, this extra difficulty adds more fuel to calls to scrap the UK’s nuclear deterrent completely.

Indirectly, the situation over trident also shows that no policy can be decided that affects a devolved nation in the UK without the express will of its people. This is true, whether the devolved nation has this right to object, as in the case of the judicial decision on Mr. Al Megrahi, or not, as in Trident replacement which should be a UK wide decision decided at Westminster. Devolution without the mutual will of the people it affects, might as well be independence.

It is ironic that the last land battle fought in the UK was between the Scottish Highlanders and British redcoats at Culloden near to Inverness in 1746. That day the redcoats won. This latest battle-cry from the Scots in Inverness may see Britain’s defence in the form of Trident’s replacement, in full retreat.