While we await the result of today's referendum, a mountain of significant lessons arises from the campaign. Accompanying the mountain is a new myth about the future of the Coalition. Like most myths that take hold while events are unfolding, it is wrong.
Let us deal with the myth about the future of the Coalition first. Good relations between Tory and Liberal Democrat ministers have been soured permanently as a result of the torrent of abuse that has poured forth. I hear or read several times a day that the Coalition is more precarious. I have no doubt that most of the anger of recent days is real, but the end of the previous relaxed amicability between ministers of two different parties will not jeopardise the Coalition. Indeed mutual wariness might lead to better thought-through policies.
This does not mean the Coalition is safe. I doubt that it will last a full parliament, but it will not be the decline in personal relations that will have anything to do with the fragility.A good guide is John Major's administration from 1992 to 1997. Personally the Cabinet got on well with each other. A lot of them seemed to have been friends since their days at Cambridge University, and they still met up for the odd dinner. But they were fatally split over policy, most specifically Europe, and the differences became unsustainable.
The volcanic personal relationship between Tony Blair and Gordon Brown, the only dynamic that mattered in the New Labour era, endured for more than a decade. The danger points always came when there were genuine and deep disagreements over policy, which happened more often than fashionable orthodoxy allows.
The tensions in the Coalition that will matter in the coming months or years will not arise because Chris Huhne accused George Osborne of lying in the campaign, or because the formidable weight of the Conservative machine turned its might with an ungrateful distorting ruthlessness on Nick Clegg. The explosion will arise over differences between the parties – if not always between the two leaderships. These tensions will be heightened if today's vote for electoral reform is lost. Last autumn a very senior Liberal Democrat described the mood of his party to me as "deferred anger". There would be patience, tolerance and perhaps a degree of enthusiasm for the relationship with the Conservatives until the referendum. If it were lost, the anger would be deferred no longer.
My guess is that vivid discontent among Lib Dems will be postponed for a little longer, but a defeat in the referendum when taken with the NHS reforms and some of the spending cuts, particularly those being imposed on local government, will lead to tensions that are far more dangerous for the Coalition than whether David Cameron and Nick Clegg end their love-in.
The painful joy of politics is its nerve -wracking unpredictability. No one knows for sure how long the Coalition will survive, but there is another false assumption associated with the durability question. If the Lib Dems were to pull out of the Coalition it is assumed there will be an immediate election. That is not necessarily the case. The Conservatives could rule as a minority government. If Cameron lost a vote of confidence Ed Miliband would have the right to seek an alternative administration and also hold a vote of confidence. Only if that were lost would an election be necessary.
This is the view of the distinguished constitutional historian Vernon Bogdanor, who is surprised that the break-up of the Coalition is seen as a trigger for an early election. All that is clear in the foggy future is that the dynamics of the Coalition change after today, and policy, not personal chemistry, will test its durability. As for the hyperbolic campaign itself, formed of deranged assertions comically at odds with an indifferent electorate, I am reminded of what a rotten device a referendum is for deciding big issues.
There is never a good time for a referendum on electoral reform. This was the worst possible. Referendums are only offered for reasons of expediency and not out of grand altruistic principle. This one surfaced in the frenzy of the indecisive election result a year ago. At the time, the general view was that Clegg had played a blinder in those sleepless days. It now looks as if Cameron and Osborne, those experts in political choreography, made the smart moves. If AV is lost they still get their side of the deal, a reduction in the number of seats, calculated with precision to benefit the Conservatives.
Why has the AV case struggled to prevail when its advocates could dance to populist tunes? Time for a change is a melodious phrase that chimes with the anti-politics mood and yet it looks as if the status quo will win.
Ed Miliband asserts that there is an anti-Conservative majority in the country. If he is correct, clear manifestation of it is proving elusive. What is obvious from the referendum campaign is that even relatively small constitutional changes require unity, coherence and authority from the advocates of reform. All three have been lacking in the Yes campaign. This is partly because the nature of the choice was narrow and the context impossibly difficult, with many on the Labour side reluctant to campaign for a change that benefits the Lib Dems. Most of the Shadow Cabinet have remained silent. Ed Miliband would not appear with Clegg. Eddie Izzard seems to have been the most prominent advocate for AV.
One of the problems with referendums is that they are contested in a specific context, and yet the result has consequences for generations. Clegg spoke an important truth when he stressed, amid the irrational levels of hostility directed at him rather than at the Conservatives, that this was not about him or the other leaders.
But that is what the referendum has partly become, along with immediate self-interested calculations. How do we harm the Coalition? That is one question commonly posed by some voters. The answer is not clear. How do we help the Conservatives? The answer is absolutely clear. Conservatives will be voting No. The clarity and unity of determined unambiguous purpose are decisive weapons when a plebiscite for change is being sought. The phrase "progressive consensus" is much used in its convenient wooliness, but reactionary forces are far more effective in getting their act together when the moment comes.
This is a big moment, much bigger than it seems. Today we have a historic chance to change the voting system, not a trivial issue. Tomorrow the consequences of the result, combined with the other elections taking place, will change politics in ways that will make the past extraordinary year seem like a calm oasis. The too-seamless coming together of the Conservatives and the Liberal Democrats obscured the stormy implications of the general election result in which no party secured a majority and a mandate. This is a hung parliament and whatever happens today will feel more hung from tomorrow.