I ran into Scotland's separatist First Minister, Alex Salmond, when he had come to meet with George Osborne, Britain's Chancellor of the Exchequer. Glowing with pride at an electoral victory that gave his Scottish National Party a vast majority in the Edinburgh legislature, Mr. Salmond had come to ask the British government for more tax and spending powers for Scotland.
I had interrupted him to ask the most Canadian of questions: What will be your referendum question? At some point in the next five years, Mr. Salmond has promised to hold a sovereignty referendum - but he had not yet said what, exactly, it would ask.
At first, he waved me off. "The wording," he said briskly, "will be produced in plenty of time for the referendum campaign." Later, I pressed him to be more specific, and his answer said much about the new realities of nationalism.
Mr. Salmond, the boldest and most canny of a new breed of European separatists, often comes across as the sort of good-humored chap you might encounter retailing tall tales in a Highland pub, and it was in this spirit that he had given a speech moments earlier.
At their meeting, he recounted, Mr. Osborne was just about to mouth the word "No" to the Scotsman's demands, when suddenly they were drowned out by the keening sounds of a Scottish pipe band rehearsing at Horse Guards Parade. "Well, now," he said, turning up his Scots brogue, "Parnell once said no one could stand in the way of the march of a nation - but stand in the way of a Scottish pipe band? How could you?"
But an hour later, leaning to me in a hallway, he lowered his voice to a whispered growl and recounted this story in much more humourless and threatening terms. "Also, incidentally," he ended, "If George Osborne says no to these very reasonable requests, he'll vastly accelerate - vastly accelerate - the movement of Scotland toward independence."
This, then, is the new political geometry of federalism. All European countries are patchwork quilts of nations and communities, stitched together through conquest and expansion (Scotland is unique in having voluntarily joined an existing federation). When times get tough, secession becomes a tactic.
For the previous generation of separatists - including Northern Ireland's Sinn Fein, the Basque country's ETA, Kosovo's KLA - independence came first, and politics second. Your followers were "a people" who possessed a de facto national identity and statehood; you simply had to order the country around you to recognize this, and wage war against those who resisted.
The new generation - Catalonia's CiU coalition, Wales's Plaid Cymru, the Scottish National Party - puts politics first. The ever-telescoped threat of separation is a means to gain more politically. The fact that only perhaps a third of Scotland's and Catalonia's voters actually want to become an independent nation can be turned to your advantage by holding out vague offers of not-quite-independence with better fiscal deals, building up "winning conditions." Needless to say, the leaders of all these parties know much about Quebec.
After much talking, Mr. Salmond spoke more honestly: The referendum, he said, would take place near the end of his elected term, possibly on the same ballot as the next Scottish election - so that the opposition parties would have the tactics of their "No" campaigns tied up with their fates in the legislative election.
And the question would neither be clear nor simple. "Actually, the question will be 'Here is a white paper, which has all the detail of independence; do you wish to proceed along the lines of this white paper and be an independent country?' he said, and continued: "It's perfectly possible to ask a second question saying: 'Here's another white paper which says maximum devolution, financial freedom - do you want Scotland to have financial freedom?' "
Wouldn't Prime Minister David Cameron's most effective No tactic, I asked, be to ensure voters that a clear Yes majority meant a complete and total break from the British federation? Wouldn't London, echoing Canada's Clarity Act, try to make a Yes vote as risky as possible?
This suggestion angered Mr. Salmond. "I actually think it's unworthy to suggest this would be the case," he said. "It's not a reasonable thing to attribute to any U.K. prime minister past or present." And besides, he said, it would be political suicide for any party that dared try it.
The next five years of Westminster politics, like it or not, will have to be a response to this challenge. I doubt anyone in Britain, on either side of the border, has any idea how nasty it will get.