At 4.30 in the afternoon of December 12th, 1969, a bomb exploded in the crowded lobby of the Banca Nazionale dell'Agricoltura in Milan's Piazza Fontana, not far from the city's famous Duomo or cathedral. Seventeen people were killed and 88 injured in the blast.
Later that afternoon, three other bombs exploded in Rome, one in a pedestrian underpass which injured 14 people and two more on the Tomb to the Unknown Soldier in Piazza Venezia, causing damage but no injuries.
The Piazza Fontana bombing, which took place 30 years ago last Sunday, has been viewed by historians and social commentators as the beginning of a traumatic 20-year period when Italy was torn apart by right-wing and leftwing terrorist activity that claimed the lives of more than 400 people. Piazza Fontana is the beginning of a murky period in Italian history, when a so-called "strategy of tension" led to the "years of lead".
This was a period marked not only by Red Brigade terrorism, culminating in the 1978 kidnapping and assassination of Christian Democrat leader Aldo Moro, but also by a series of bomb attacks, allegedly carried out by right-wing elements, of which that at Bologna train station in August 1980, killing 85 people, was the most serious.
Last weekend, the 1997 Nobel prize-winner for literature, playwright Dario Fo, along with his wife Franca Rame, chose to mark the unhappy anniversary of Piazza Fontana by leading a train tour across northern Italy and down to Rome. Called "The Train of Memory and Pain", Mr Fo's anti-terrorist caravanserai made significant stops on the way.
First, there was Piazza della Loggia in Brescia, where eight people were killed and 90 injured during a trade union rally in May 1974; then Milan in memory of Piazza Fontana; and they stopped at Bologna, in memory not only of the 1980 train station bombing, but also of the August 1974 attack on the Rome-Munich express train in which 12 people died and 40 were injured.
Relatives of those who died in Piazza Fontana remain distressed 30 years later, the bombers go unpunished, while a new trial on the massacre is scheduled to start next February 16th. Likewise, no one has been sentenced either for the Bologna train station attack or the June 1980 Ustica air disaster: 81 people died when a scheduled flight from Bologna to Palermo exploded in mid-flight, apparently hit by a missile.
Italy's inability to shed light on some of the mysteries of the last 30 years remains a matter of concern. Even Senator Giovanni Pellegrino, president of parliament's permanent "Massacres Commission", had to concede last weekend that it was probably too late to obtain justice regarding Piazza Fontana, saying: "Justice 30 years later is but a surrogate."
Senator Pellegrino was among those who last weekend called for the lifting of "state secrecy" on all documents relative to the terrorist years. That call is prompted by the suspicion that the Italian state has been responsible for covering up the truth. High-ranking politicians, soldiers, members of the illegal Freemasonry lodge P2, along with Italian, US and other secret services, may well have orchestrated the "strategy of tension" to discredit the left and push voters to the right, when the Italian Communist Party was reaching an all-time high in electoral support (34.4 per cent at the 1976 general election).
The right-wing bombing campaign, too, had the obvious intention of prompting a tit-for-tat retaliation from the left. If a number of former Red Brigade activists are to be believed, these tactics worked, since many leftwing terrorists point to the Piazza Fontana bombing as a turning point.
While such theories might seem fanciful at first, it is worth recalling one undisputed fact to have emerged during the last 30 years. Namely, that Italian secret services worked hard to prevent investigators finding out the truth about many of the allegedly right-wing attacks. In the cases of Piazza Fontana, Bologna train station and Ustica, senior secret service officers or agents have been convicted of depistaggio - wilfully misleading an inquiry.
Curiously, the fight against the left-wing Red Brigades was much more successful.
It is also worth recalling the admission made by CIA director William Colby to journalist Philip Willan in the book, Puppet Masters, the Political Use of Terrorism in Italy. CIA director from 1973 to 1976, Mr Colby admitted that he had been sent to Italy in the 1950s "to run what was by far the CIA's largest covert political-action programme undertaken until then, or indeed since". Mr Colby cheerfully conceded that his task had been to prevent Italy "being taken over by the communists".
Dario Fo's "Train of Memory and Pain" and last weekend's public meetings serve to remind us that, 30 years on, Italy still pays a high price for its once strategic position on the Iron Curtain frontier, a position that saw Italy become a violent mini-theatre for the Cold War in which terrorists, secret service agents and politicians acted out a tragic, sometimes farcical and often meaning less struggle.