Nearly 30 years after the great flood that brought home to the world the fact that Venice could go under the waves, the Italians are still trying to decide what to do about it.
With the advantage of hindsight, we can see the disaster of 4 November 1966 as the first warning rumble of global warming, nature clearing its throat prior to telling us loud and clear that the whole planet was in dire trouble. And Venice, built on millions of wooden piles in the lagoon barely above water level, was the canary in the coal mine: the first European victim.
It was on that day in November 1966 that a rare combination of abnormally high tides, rain-swollen rivers and a fierce Sirocco wind filled the Venice Lagoon to bursting and sent floodwaters thundering through the canals to a height of 6ft 4in.
It was the worst flood in the city's history. Thousands of residents were pinned in their homes for days, and art works valued at $6bn (£3.2bn), stored on ground floors or in cellars, were ruined. Venice, neglected and quietly rotting ever since the defeat of the Venetian Republic by Napoleon more than a century and a half before, was suddenly recognised as a city in dire need.
Help, advice and money poured in, and a debate began on how to keep the flood waters at bay. The tide of 4 November may have been unique, but damaging tides of less dramatic proportions had over the preceding decades become an annual reality. What was needed was a way to keep them out.
The man-made Venice Lagoon has three inlets from the sea. The industrialisation of the lagoon during the 20th century, the destruction of sand banks and their replacement by concrete ones, and the digging of canals to allow big ships to enter, have made the lagoon far more vulnerable to floods, experts say. Conditions inside and outside are today more or less the same.
The only practicable way to keep out the high tides, engineers decided, was to have gates fixed to the lagoon floor that would hinge upwards to close it off to at times of emergency. And so the Moses scheme was drawn up, envisaging 78 massive gates, each 28m wide and 18m long, fixed to the lagoon floor.
The politicians then sat down and chewed the idea over. For the best part of 30 years. There were a hundred different views on the project, and the damage it could do. It wouldn't work at all. It would cause the lagoon to fill with stagnant water, it would kill of the lagoon's ecological diversity. It was a scam by capitalist corporations to make a killing at the city's expense. Governments in Rome came and went - at the rate of about two per year - without taking the difficult decision.
Finally, three years ago, then Prime Minister Silvio Berlusconi cried "Basta!" and set the project in motion. The first stone, bearing his name and ceremonially set in place by him, is now at the bottom of the lagoon.
Mr Berlusconi was mad for his grands projets, the most pharaonic of which was the plan to build the world's longest single-span suspension bridge from Calabria to Sicily. But Moses was not pharaonic, it was merely necessary, and very, very long delayed: every year the number of days in which life in Venice ground to a halt due to acqua alta (high water) was increasing.
Finally, the project got under way. Yesterday the firm set up to run it, Concorzio Venezia Nuova, said that it's going well - 25 per cent of the work has been done, and out of a total cost of €4.1bn (£2.8bn), €1.58bn has been received and €1bn spent. Moses is due to be completed by the end of 2011.
At least, that was the completion date until yesterday. But now the project has been thrown into utter uncertainty. The Italian politicians are at it again.
Moses became Mr Berlusconi's baby, which obviously makes it fair game to the other side when they get into power, like other babies of his. (The far more questionable Messina bridge is almost certainly for the scrap heap). But the specific problem in Venice is that one centre-left mayor, Paolo Costa, who favoured the gates, has been replaced by another centre-left mayor, Massimo Cacciari, who doesn't. A member of the centrist Margherita ("Daisy") party, his stand is strongly supported by the unreconstructed communists of Rifondazione Comunista, and by the greens of the Verdi party.
Mr Cacciari, a professor of philosophy by trade whose black-eyed, heavily bearded, brooding presence lends gravitas to many television current affairs programmes, has been Mayor of Venice once before. During his last stint several years ago, his advice to his citizens regarding the acqua alta was "go out and buy gumboots". His opposition to Moses has always been firm. And yesterday, under his guidance, the Venice government decided to urge Rome, which has the final say on what happens to the Moses project, to undertake a thorough re-examination of the whole thing.
Now the decision on what to do about Moses goes to a grand government committee involving Transport and Infrastructure and other ministries, before the government decides how to proceed.
Supporters of the project hope it will soon be back on track - centre-left governments before 2001 had backed it, and Prime Minister Romano Prodi, confronted by opponents before the election, asked them, "What possible alternative is there?"
But there will now be a delay. And for the ordinary people of Venice, delay means disaster. It's unacceptable. "Life in the city is already next to impossible," Graziano, a Venetian born and bred, said yesterday. "The quality of life in Venice is very low and getting lower. For many people this is the last straw."
Quality of life in Venice - low? Venice remains one of the most delicious destinations in Europe, with its wall-to-wall upmarket boutiques, posh hotels, gorgeous churches, its galleries and museums, and Harry's Bar full of people in linen cream suits drinking Bellinis. Venice is the playground of the rich, how can it be so bad for the poor?
The fact is that Venice has been experiencing a drastic, high-speed hollowing syndrome that will probably only cease when the last real Venetian has decamped to Mestre, just across the water. With its absence of motor traffic it has always been a highly inconvenient town in which to live (as opposed to popping in for a visit). It's also very expensive, and with the arrival every year of more tourists that gets worse and worse.
In 1950 the population was about 184,000. Now it's down to one-third of that, and still shrinking. And it's a vicious circle. The more people leave, the more ordinary amenities like grocery shops and bakeries disappear with them, making life more difficult for those that remain. Venetians are becoming strangers in their own home town.
British economist John Kay, the author of The Truth About Markets, has recently argued that Venice can only be saved by being run like the theme park it is increasingly becoming. "An enterprise that is used to provide entertainment for the masses is best placed to run the city," he says.
But such a cynical argument ignores the fact that more than 60,000 ordinary Venetians continue to live in the city, providing its real flavour - even if they seem to be increasingly neglected by the authorities.
The flight from Venice helps to explain, according to Graziano, why the majority on the city council is anti-Moses. "Twenty years ago the Christian Democrats held mass rallies of Venetians demanding that the sea gates get built to stop the flood waters. That doesn't happen today because the demographic balance has shifted.
"Now the mass of voters are over in Mestre, and they are not threatened by the floods. So they don't care about Moses. And so the debate gets hijacked by environmentalists who raise a noise about the damage to the ecology of the lagoon - but the lagoon is an artificial creation, man created it and has constantly modified it. It can't be right to say we don't lay hands on it any more. That's just menefregismo!" - "don't-care-ism."
Britain's Venice in Peril fund has been involved in the city since the great flood of 1966, and has been campaigning for the building of the gates for many years. Three years ago, they hosted a major conference in Cambridge with 130 scientists from many different countries. The overwhelming verdict was that Moses is a must.
Yesterday the chairman of the fund, Anna Somers Cocks, said that with global warming threatening unprecedentedly high rises of water levels all over the world, "nobody can be sure how high the water is going to rise".
"During the conference, one of the Dutch scientists said that Moses 'will only buy the city some time'. The Intercontinental Panel on Climate Change (IPCC) is predicting rises of between nine and 88cm in this century, which is an enormously wide span. Nobody knows for certain what the result will be in the Adriatic. Moses is designed to be able to withstand a rise of 16 to 25cm.
"But what is ridiculous is that people should still be discussing issues which are already beyond doubt. Rowing over the gates takes up the political energy that should be devoted to deciding what is to be done next."