As expected, Jeremy Corbyn was re-elected as leader of Britain's Labour Party over the weekend. Thus ended the attempt by the bulk of Labour's parliamentary party to remove him. There is much comment in the usual places that this will be a disaster for the party, and by and large I agree. But we are missing the wider significance. Mainstream Westminster politicians are losing their grip on politics. Wise politicians will need to change tactics.
Ironically enough, the heart of the MPs' challenge on Mr Corbyn was that he was incompetent. That may be true, but the MPs' attempt to unseat him failed to show any serious political competence itself. It is interesting to speculate as to why professional politicians should be so comprehensively outmanoeuvred by the amateurs. Britain's electoral system does not in fact encourage serious electoral competition by its leading politicians. Most MPs are elected to safe parliamentary seats - so the main political skill is getting selected in the highly competitive, but internal, process of choosing candidates. Advance after that comes through ministerial or shadow ministerial promotion, which is even more about schmoozing that cut-and-thrust. When faced with a serious electoral challenge amongst a mass audience, MPs are often ill-equipped. This was demonstrated dramatically by Labour in Scotland, rich in formerly safe Labour seats, when they proved quite incapable of handling the SNP surge in 2015. It is also why there is little prospect of the MPs breaking away to form their own party - they don't have the nous.
This is not so true of the Lib Dems, whose seats are much more competitive, with an important exception. In 2005 many Lib Dem seats really were safe, and were successfully passed over to politicians with little experience of hand-to-hand politics. These included Nick Clegg, David Laws and Chris Huhne, who then proceeded to take over the party's leadership in parliament. The former, at least, proved ill-equipped for serious political competition.
But it hasn't just been the MPs who have been routed. Their professional advisers (who like to style themselves as "strategists") have been proved wanting, for all their clever talk. The Lib Dems are sore about the coterie of advisers that Mr Clegg surrounded himself with. Labour Leader Ed Miliband's fared little better in 2015. The Conservatives' David Cameron clearly felt they had cracked it. Relentless negative campaigning had seemed to win the day in the Scottish referendum in 2014, and for the Tories in 2015. But it fell apart in the Remain campaign in the EU referendum, against a Leave campaign that was sparky but distinctly amateur. Meanwhile the rout of the professionals is being perpetrated by Donald Trump in the US, to say nothing of Mr Corbyn's impressive victories in 2015 and 2016.
What accounts for this? Mainstream politics has lost its appeal. Perhaps it is too defensive. By and large the easy way to win elections is to undermine your opponent - but this has the long-term effect of undermining all politicians. Then there are the inevitable compromises of office, as the complex problems of the modern world will not yield to quick solutions. And the checks and balances of democratic politics mean that politicians have to cooperate with people they disagree with in order to get anything done, be that within parties or between them.
And then there is the fact that economic development does not seem to be going so well in the developed economies. Globalisation and technological advance helped roll back poverty in the developing world, and raise living standards for many in the rich countries too, but there were significant losers, who feel let down by their leaders. Then there was the economic crash of 2008/09, which showed that much of the economic growth in the previous decade was a mirage. Since then the developed world has been stuck in a period of low growth that mystifies economists - though many explanations are offered (poor macroeconomic management; inequality; the wrong sort of technology; demographic changes; reversing gains from trade; too much regulation; too much greenery - each has its fans). Confidence that mainstream politicians know what they are doing drains away.
And people are getting fed up. Exploiting this fed-up-ness lies behind the success of the amateurs, like Mr Trump, Mr Corbyn and the Brexit campaign. This has a very dark side. These campaigners may be sparky, but their main weapons are destructive memes, which bear little relationship to the truth. Indeed it is often referred to as post-truth politics. It doesn't seem to matter what Mr Trump or Mr Corbyn says, his followers lap it up. Many of them know that a lot of it is untrue, but they love to give the other side a beating. That may be a bit harsh on Mr Corbyn, who is nowhere near the Trump or Brexit league of untruth, but his supporters seem unable to engage with adverse evidence, especially about the electoral appeal of their policies. The rise of modern media makes it very easy to live in a bubble of like-minded people who avoid checking their beliefs with reality. It is ironic that these same people accuse professional politicians of being in a bubble of their own. Actually polling, focus groups and various other techniques of politics make modern politicians more informed about popular feelings than most. It doesn't help.
What to do? All this brings to mind Visconti's film of Lampedusa's novel The Leopard about the struggles of the Sicilian aristocracy during the Risorgimento (and perhaps my favourite film ever): "Everything must change so that everything can stay the same" says the leading character.
Some, like the FT's Janan Ganesh, urge staying true to old-fashioned, pragmatic politics that the Conservatives have made their own. That is unappealing for those on the liberal left and centre. It means giving ground to the narrow-minded.
Instead I have to draw deep on my liberal optimism. Deep down people understand the truth, and will put up with lies only for so long. That is how Soviet Communism was destroyed. It is why the BBC brand remains so strong - look at the hoo-ha over Bake Off. Liberal politicians must stick with it: don't play the dark forces at their own game.
But they must do more. They must be exciting again. They must discover new ways of tackling the modern world's problems, and sell them to the public. To be fair to Mr Corbyn, this is part of his appeal, though he harnesses the dark, post-truth side too, and a lot of his ideas look like 1970s nostalgia. But some of his supporters seem willing to search for new ideas. Never has this been so important.
Slowly the liberal left is finding these ideas. A new constitutional settlement for more inclusive and devolved politics. An economy less dependent on big corporations. Environmental sustainability being at the centre of the way we think, rather than endless attempts to expand consumption. Education for all that promotes modern skills and wellbeing. Public services that solve human problems rather than applying inappropriate big-industry models. Celebrating cosmopolitanism rather than give in to inward-looking nostalgia.
This thinking has to be finished and turned into an exciting synthesis that people from across political parties can take up, and which will appeal to the sceptical. Bridges must be built between the more open of the Corbynistas, the Labour centrists, the Lib Dems and the Greens - and not forgetting liberal Tories and Nationalists too. Surely that is our best hope.