The cameras captured them in all their odious infamy.
Masked men with their arms outstretched, adopting idiotic Messianic poses as they basked in their violence.
The Croatian "supporters" set off flares in the San Siro stands, a couple of which caught fire. They also threw flares onto the pitch, forcing the Italy-Croatia game to be halted several times (yesterday morning, Singapore time).
Other masked cowards, their faces obscured by hoods or scarves, jumped and whooped, celebrating their flare-throwing leaders like an outtake from the Planet of the Apes.
In such moments, football becomes an indefensible sport that's very hard to like.
Croatia should be kicked out of the Euro 2016 campaign for the brutish, repugnant behaviour witnessed in the San Siro.
But, of course, nothing of the sort will happen.
There is already vague talk of Uefa taking action and half-hearted murmurs of sanctions, neatly underscoring the contemptible attitude that still exists.
The game comes first. Nothing slows, much less halts, the juggernaut.
Whether it's blatant, systemic corruption along the cosseted corridors of Fifa or vile hooligans bringing their domestic grievances into a family sports arena, the game goes on, unabashed.
Former Croatia forward Goran Vlaovic suggested the flares and the subsequent fighting might have been a protest against the Croatian Football Federation.
But everyone is complicit. Every football report on the match has been inadvertently complicit. You and I are complicit.
Despite the shocking TV images and the disregard for families who were at risk of being caught up in a fire, attention inevitably returned to the contest itself.
Yes, those hooligans were terrible... Meanwhile the point leaves both sides joint-top of Group H with 10 points.
Yes, the Italian police were heavy-handed with their truncheons, providing chilling footage not witnessed in British football for decades... But Gianluigi Buffon dropped a real clanger for Croatia's equaliser, didn't he?
Yes, the hostile atmosphere deteriorated so quickly that the referee had to take the players off for 12 minutes to allow riot police to restore order, but the Croats have got real problems. Luka Modric picked up an injury.
Frankly, the coverage has been nauseating, revealing either a cold-headed detachment to inhumane behaviour or an eagerness to gloss over unsavoury incidents, like aunties praising a successful wedding and choosing to ignore the drunken uncle who threw up over the bride.
A sport's ethics and its unspoken code of conduct are ultimately undermined not by anger or violence, but by indifference. When seething rage gives way to shoulder shrugging, the moral compass is shattered.
Modern football is already perilously close. Only now are Sheffield United grasping the depth of the public outrage at the possibility of re-employing convicted (and unapologetic) rapist Ched Evans.
Over at the farce formerly known as Fifa, the breathtaking extent of the corruption allegations continue to be drip-fed to the public only to be met with the same universal reaction... It's Fifa, what did you expect?
Likewise, hooded thugs disrupt a game, practically set fire to a stand, throw flares at professional sportsmen and traumatize children and are met with the same generic response... It's European football. What did you expect?
So we then mostly ignore them. We pretend they weren't really there (as they aren't in just about any other professional sport you care to name).
The focus quickly shifts to Modric's injury and Italy's lack of both firepower and midfield creativity without Andrea Pirlo.
Some might say these belligerent buffoons thrive on the oxygen of publicity. Why give their feeble egos what they so desperately crave?
So do not publicise then, just penalise. Deny them a stage to perform. Kick out the federations who pay lip service to addressing their social problems, but continue to take the hooded clan's cash at the turnstiles.
Modern football is already an inorganic machine with a warped photosynthesis process. It sucks in morality and spews out money.
And the obvious haste to move on from the Croatian crowd trouble and return to the game itself feels like another distasteful attempt to get back "on message".
But the football played between Italy and Croatia really doesn't matter here. Only the violence does.
It would be reassuring to think the game's authorities might agree.
This article was first published on Nov 18, 2014.
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