The great, green vault of Celtic Park was, as promised, transformed into the taut bearpit that drew Irish blood. It was the night Gordon Strachan had prophesised, a gathering of Scottish clans keyed to almost unhinged emotion as they claimed critical Group D momentum.
Shaun Maloney's 74th-minute goal was celebrated as if the sky was raining money over Glasgow's east-end. To some degree, it was.
We got 'Flower of Scotland" to a banshee shriek, we got The Proclaimers and their 500-mile walk, we got the sense of a whole nation sticking its chest out and announcing itself ready to take on the world.
It was, thus, everything Martin O'Neill had hoped to avoid, a defeat that largely neutralises much of the momentum gathered by that late equaliser in Gelsenkirchen.
The 'Boys in Green' still sang as they always will, but you could sense a black wind blow through Irish chests here. A sense of reality crowding in.
Grant Hanley did head against his own crossbar in the dying flurries, but this always had the bawdy tenor of a special Scotland night
It was hard to begrudge them too, given their international story is just one, long ghostly trail of heartache.
Their finest team, the side of Souness, Gemmill, Hartford, Macari and Dalglish, floundered on the rocks of eccentric management. Ally MacLeod took them to Argentina in '78, peddling the notion that they could win the World Cup. With this view of the world unblemished by modesty, MacLeod talked the talk of a fight promoter, peddling an idea his players always feared might be more suited to the panto boards.
So it came to pass.
Ally's congenital weakness of picking the wrong team eventually backed Scotland into the unpromising corner of having to beat Holland by three goals to avoid elimination.
Famously, they came up just short of that miracle in Mendoza, Gemmill's wonderful, slaloming goal still celebrated in these parts as a haunting glimpse of what that Scotland side could have been.
So, to this day, MacLeod stands as a kind of poster boy for the self-destructiveness written into Scottish football's DNA. As if in his honour, support for the national team swings between excesses of hubris and ambivalence.
That support comes largely from places other than the vast, belligerent 'Old Firm' houses, where - even in light of Rangers' current humiliation - life still bristles with a cleaving simplicity. It is from towns like Aberdeen and Dundee and Motherwell that last night's 'tartan army' assembled, "Different people" as Gordon Strachan put it.
Well those people had their say here.
From his first touch, Aiden McGeady was assailed by great, angry roars of protest at his perceived infidelity. He looked anxious as a jack-rabbit, Scottish studs snicking, scissor-like, at his ankles from first whistle.
It was nothing especially violent, just the honouring of a contract. A wave to the trumpeters at a bullfight. Within six minutes, he had snapped back, tripping Andrew Robertson to an eruption of outrage that might have been more appropriate for a child killer.
Then, on 15 minutes, the decibels rose even higher for a poor challenge on Steven Fletcher that earned McGeady a booking.
The game had a roster of little dramas, without ever quite rising above the ordinary.
It almost exploded into life in the 33rd minute when Charlie Mulgrew headed Shaun Maloney's cross just wide under significant pressure from Seamus Coleman.
Momentarily, the Scots seemed emboldened, Steven Whitaker drawing a smart save from David Forde and Fletcher then just failing to get what would surely have been a scoring touch to Maloney's right-wing cross.
No question, the momentum was with them now, but there was still a good deal more haste than method to it all.
The Scottish people love Strachan because he has moved the team away from the pad-locked caution of his predecessor, from an innate pessimism that once had Scotland playing in the Czech Republic with six midfielders and no striker.
Still, the desire to find respectable distance from the Celtic-Rangers insularity was palpable in every Strachan utterance this week. He became irritable as a teething baby when asked about the Celtic Park atmosphere on Champions League evenings.
The venue, he stressed, had been chosen only for its capacity. Nothing philosophical to the decision. Nothing spiritual.
Yet, this is a ground over which the Irish tricolor has always flown. A place that fought for the right to do so when the Scottish FA sought to have it taken down. This is a stadium impregnated with such an Irish connection that the idea of bringing Martin O'Neill and his team here seemed, well, eccentric.
It had to be bursting with memories for O'Neill especially last night. He tends to carry himself like a startled academic now, but life at Celtic did not always allow that. The 'Old Firm' day he threw his arms around a red-carded Neil Lennon, making that clenched-fist march to the Celtic end of Ibrox, was a day he lost himself utterly in the emotion Glasgow ignites in football people.
He was animated again last night, waving his arms furiously at the ease with which Scottish players went to ground. isn't a man overly susceptible to sentiment as last night's team-sheet illustrated, no place for Robbie Keane on his return to the great, green cathedral.
It seemed to make sense too, Shane Long and Jonathan Walters combining well in the early stages.
At times, they seemed close to something incisive, but the co-ordination was always fractions off. Once, Steve Walford called Long to the touchline for an impromptu workshop, but it wasn't so much the right movement they were lacking as access to a locksmith.
Some wonderful McGeady trickery almost got Walters in on 51 minutes and, moments later, Long's header was just too close to David Marshall after Walters's clever flick.
Then McGeady went close too and the 'Fields' began to ring down from the tiny corner of the main stand formally allotted to the Irish.
But the game was always hanging on a fragile hinge and, on 68 minutes, O'Neill's decision to send on Stephen Quinn and Robbie Brady seemed to carry a mixed signal. The Irish supporters were chanting 'Keano', that too open to interpretation.
Walters headed onto his own crossbar just seconds before Maloney curled home that kill-shot, sending the bedraggled Irish home tae think again.