He has, he says, lost touch with his constituents: “Those people must think nationalism and independence is a really big thing. That’s what I don’t understand. The democratic process has a way of correcting itself. If I am a person who doesn’t understand his former constituents then it’s good that they are former constituents. I don’t think I’m qualified to be an MP now.”

Soon after talking to me, Harris is fired on stage. The swing to the SNP among the people he has represented since 2001 is 34 per cent, a swingometer-busting number but typical of the punishment meted out in the Emirates arena in the early hours of May 8. All seven Glasgow constituencies went from Labour red to SNP yellow.

The extremes of emotion felt by those in the hall are confirmed by a bearded, hunched man with an SNP badge fixed to his baggy blazer. “I’m quite enjoying other people’s suffering, which isn’t like me,” he says. “I’m not one for schadenfreude, but Labour had it coming.” He is standing apart from the mob of nationalists that have collected around Sturgeon. “This whole thing is so surreal . . . but I suppose she’s a celebrity now,” he says.Norman MacLeod, an SNP councillor for Pollokshields in the Southside of Glasgow who nods as he speaks like a man who has just been proved right, tells me, “We’ve been at it for more than 80 years. It’s our time now.” He doesn’t think the Union will last much longer. “Make no mistake,” he says “the referendum [which the pro-independence side lost] was the first step to independence. Tonight is the second.”

As the remaining Labour MPs are formally dethroned, SNP politicians who not long ago were foot soldiers in a fringe movement find themselves Members of Parliament. Their acceptance speeches are rigorously on message. The audience is treated to tales of “Tory cuts”: sobering stuff at four in the morning. Natalie McGarry, the newly-elected MP for Glasgow East, dedicates her victory to “every mother who has queued for a food bank, every member of the disabled community who has had benefits slashed, and  every lone parent who has suffered at the hands of austerity.” (She fails to mention the fact that her boyfriend is Glasgow’s sole Conservative councillor.)

News from south of the border makes much of this euphoria academic. The unexpected Conservative majority puts the value of SNP clout in the House of Commons at, well, zilch. Cuts will continue, whether the SNP likes it or not. And some do like it. On hearing the exit poll numbers earlier in the night, an SNP supporter watching the results at central Glasgow’s Yes Bar — independence lager is on tap — described the news as a “dream result”.

“Scotland won’t want to take another five years of the Tories,” he said. “We’ll be gone by 2020.”