Scotland referendum no longer about keeping calm and carrying on

You know the gloves are off when the typically stiff British prime minister suddenly feigns using the F-word in public.

But David Cameron was wisely playing to his audience. "Effing Tories" is probably how many in Scotland would describe his party, too.

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His seemingly off the cuff, slightly self-deprecating remark in Edinburgh Wednesday was part of a speech that revealed an impassioned or desperate, depending whom you ask side Cameron has scarcely shown before in public.

Most would still agree, a week before an independence vote that could end the 307-year union, was probably as good a time as any to show it.

"People can feel it is a bit like a general election that you make a decision and five years later, you can make another decision: if you are fed up with the effing Tories, give them a kick and then maybe we'll think again," he said to audible giggles.

"This is totally different to a general election: this is decision about not the next five years; it's a decision about the next century."

And yet you would have scarcely noticed a hint of concern in London before last weekend, when new polling numbers put the Yes side ahead for the first time since the campaign started nearly two years ago.

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Now, the academic argument that the rest of the United Kingdom has no say in Scotland's decision has been tossed out.

Instead, panic has set in, of the sort this country hasn't seen in a generation: The kind that has pondered an intervention by the Queen, and has even prompted questions to the head of the Bank of England Canadian Mark Carney asking for "reassurances" for the jittery.

Carney revealed the bank has made "contingency plans" to ensure financial stability whatever the outcome. He would not elaborate.

'Don't tear it apart'

The conversation now breathlessly covered by newspapers and broadcasters has suddenly turned urgent.

The alarm compelled a plethora of politicians, former and current, to descend on Scotland, figuratively and literally voices that include former prime ministers John Major and Gordon Brown.

All three current major party leaders fanned out there yesterday, to do their part to save the union. In that Edinburgh speech, an uncharacteristically emotional Cameron said a broken union would break his heart.

"Our union is precious. Don't tear it apart," he also wrote in a letter published in the Daily Mail yesterday, practically begging the people of Scotland to stick around.

Canadians will of course remember that 11th-hour embrace in the dying days of the 1995 Quebec referendum campaign, when tens of thousands of Canadians answered a call from the No side and flocked to the province to implore Quebecers to vote no. It did not go over well with separatists.

If it all does sound familiar, don't be surprised No campaigners are apparently taking pointers from quiet Canadian advisers.

Visits could backfire

Though no huge rally is materializing here yet you can imagine how separatist Scots are reacting to London's last-second love in.

Head of the Yes side, Alexander Salmond, said it only helps him.

"They're not popular in England, never mind in Scotland," he says. "So yes, I think it's a boost for our campaign."

The state of the Union is certainly testy. Many, however, agree, no less on the No side and wonder about the wisdom of deploying those politicians in a region that finds most of them alienating.