The four-times winners of sport's greatest prize have not suffered the agony of missing the finals since the 1958 edition in Sweden.
But sitting out next year's tournament in Russia is a real possibility after a 1-0 defeat in their play-off first leg in Stockholm on Friday.
Under-fire coach Gian Piero Ventura insists the Azzurri have sufficient quality to turn the tie around - a view that seemed to be shared by fans strolling around central Rome on Monday afternoon.
"Not winning is completely unthinkable, basically something that has never happened before. For Italy, getting to the World Cup finals is almost a duty.
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"Of course there are many more important things going on in Italy, but, certainly, in sporting terms it will be a big drama because in the past we have always qualified and we have often won."
Italy ended up in the play-offs as a result of finishing second in their qualifying group behind Spain and a sluggish performance in Stockholm has compounded the task of reaching next year's finals in Russia.
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The first leg was a scrappy, physical affair with Sweden edging it thanks to substitute Jakob Johansson's deflected shot just after the hour mark.
"They're playing miserably at the moment but Italy still has a good set of players in my opinion," said another Rome resident, Enrico Doddi.
"It is all down to mentality: if Italy can convince itself it has strong players it can make an impact at the World Cup. And we have to start tonight.
"You cannot have a good World Cup without Italy."
Another fan, Manuel Sanna, said failure would be a massive blow to the country's morale, extending beyond the confines of sport.
"Football is very important to us, we are brought up with the passion for it. I'm hoping for an Italian football renaissance along with an economic one."
Amid the prevailing anxiety, Turin mayor Chiara Appendino struck a lighter note by tweeting a picture of herself in an Italy top and "Losing is not allowed,' emblazoned across the image.
In a reference to Sweden's most famous export, IKEA, the mayor tweeted: "They're famous for making their homes welcoming, it would be a shame not to send them back to them."
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Enrico Addati, a teenager from Bari in southern Italy, told AFP: "We are all very anxious. I just hope that the squad can produce the sense of honour and especially the heart they will need.
"The prospect of failure is really not very nice. Italy can't not be at the World Cup.
"For sure there will have to be resignations if that happens. But we don't want to get to that point. We have to be at the World Cup and fighting to win it."
Neapolitan schoolteacher Laura Sobrero said coach Ventura had to accept responsibility for Italy having been left sweating until the last minute.
"It will be awful if we don't get to the World Cup because we are so used to being there and it being a very intense experience for the whole country.
"Italy not being there will almost be like an offence to the fans, so let's hope we can do it. Football is in our blood.