The Italians face a hard time stamping out football hooliganism.
Nelson Dida lies prostrate after being felled by a flare
Because stamping out the so-called "English Disease" means cracking down on the ultras, the hardcore fans.
The ultras have been responsible for stabbings and beatings, not to mention racist chanting and the endless production of inflammatory banners.
They are also very powerful, in some cases so powerful they can influence club policy on a wide variety of issues, such as team selection and player signings.
The authorities have an increasingly hard time keeping them in check, so much so that the police refuse to enter the "curvas", the areas in a ground where the ultras congregate.
There is even evidence the ultras control entry to their part of the stadium, hence the reason so many flares and fireworks end up in the ground.
Inter's fans are some of the worst, as Tuesday's events in the San Siro testify.
With their team heading out of the Champions League, they began throwing flares on to the pitch, one of which struck Milan goalkeeper Nelson Dida.
With the trouble showing no sign of abating, the match was eventually abandoned.
Less than 36 hours before the trouble, the Italian government pledged to crack down on hooliganism after 85 policemen were injured in skirmishes at five matches last weekend.
The move backfired spectacularly.
In fact, any threat to stop the troublemakers has failed to have the desired effect.
In 2001, Inter were ordered to play two European games away from the San Siro after fans caused the abandonment of a Uefa Cup tie with Spanish side Alaves.
The Serie A giants were also fined £33,000.
Did the punishments have any effect? Make up your own mind.
Just a few months later, during a game against Atalanta, Inter fans torched a visiting supporter's scooter and threw it from the second tier of the San Siro.
And a fortnight ago, supporters of Inter and Verona clashed during Italy's World Cup qualifier against Scotland, also at the San Siro.
Scottish Football Association chief executive David Taylor described the scenes as the worst he had seen in 20 years.
It's not just Inter's fans who are the problem.
Earlier this season, Swedish referee Anders Frisk was struck by a coin during Roma's Champions League game against Dynamo Kiev.
The match was abandoned and Roma told to play their next two group games behind closed doors.
But, as the Italian government admits, imposing such a penalty rarely works.
"Certain fans regard the closure of their ground as a victory, something that makes them feel more important," explained Italian sports minister Mario Pescante.
"What we need are quicker and tougher sanctions to cut down the incidents, especially since it is the boys in uniform who are hurt the most in these clashes."
Blood pours from the forehead of Swedish referee Anders Frisk
After Tuesday's events, Italian Prime Minister Silvio Berlusconi, who is also the owner of Milan, threatened the "most drastic measures available" to combat hooliganism.
And on Thursday, Franco Carraro, the head of the Italian Football Federation, said games would be abandoned if objects were thrown from the stands.
The team whose fans were to blame would then be penalised with an automatic 3-0 loss.
It is a start, but will it be enough to stop the ultras?
Or will Uefa be forced to employ a stiffer punishment, like a blanket ban on Italian clubs competing in Europe?
English clubs were hit with such a suspension after 39 Juventus fans were killed prior to the 1985 European Cup final against Liverpool.
Obafemi Martins looks on as the flares hit the San Siro pitch
The move was unprecedented and forced the Football Association to take a serious look at the hooliganism issue.
Now, thanks to the introduction of closed-circuit television, computer databases monitoring known troublemakers, undercover police operations and membership schemes, the English game is in a much better state.
The Taylor Report, published after 96 Liverpool supporters died at the FA Cup semi-final against Nottingham Forest, also had a major impact on problems at English grounds.
The Hillsborough tragedy, which occured exactly 16 years ago, had nothing to do with hooliganism, but it led to the introduction of all-seater stadia, which prevented supporters from massing in one area, much as the ultras do now.
Perhaps all-seater stadia would help combat the ultras.
But some action is needed, even though world governing body Fifa is apparently unsure just how serious the problem is.
In an interview with Radio Five Live, Fifa vice-president David Will said he hoped Tuesday's trouble was "just an isolated case and not something that is going to be repeated".
In the same breath, he also admitted that "there have been a lot of problems - or more problems - in Italy than perhaps in other countries".
Whatever its viewpoint, Fifa is happy to let Uefa take the lead - for the time being.
And whatever tactics Uefa and the Italian authorities eventually employ against the ultras, it promises to be a bitter battle.
But as Milan's Gazzetta dello Sport put it in the aftermath of Tuesday: "Words are no longer enough."