Political tribalism has been around for as long as politics itself, and people have been complaining about it for just as long. Plato, in the Republic, has Socrates bemoan the tendency of legislators to act out of factional interests rather than duty – though his solution to the perpetual cycle of timocracy, oligarchy, democracy and tyranny was a philosopher king, and as yet there’s no great popular clamour for putting Roger Scruton or AC Grayling in Downing Street.

But however disagreeable party politics are – and it could only be very dull, and probably dangerously stupid, people who would align themselves with every dot and comma of any party’s manifesto – things become even more volatile when parties break down and realign themselves.

That’s happened fairly often; the Whigs, originally a party designed to protect aristocratic interests against royal power, gradually became more supportive of the mercantile classes, and was then divided by radical and liberal ideas on rights and economics. The Tory party was similarly split by its internal differences on the repeal of the Corn Laws. The reinvention of the Labour Party under Tony Blair, when it ditched Clause IV, is recent enough that there is now an effort, among at least some of Jeremy Corbyn’s acolytes, to reverse it.

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One of the by-products of Brexit, quite separate from the merits or deficiencies of its central issues, has been to create fissures in the two main UK parties and, quite possibly, a moment of realignment as significant as those historical examples. The Newport West by-election saw a huge drop (even for a by-election) of 20 per cent in the share of the vote achieved by Labour and the Conservatives combined.

The weekend’s opinion polls, by YouGov and Opinium, indicate that the Tories are now at their lowest point for at least five years, at 29%. If you want an indication of how bad that is, it’s almost exactly the share of the vote they got in Scotland at the last election, which suggests wholesale desertion in those areas of the UK that have traditionally been strongholds.

Given the ineptitude of the party’s current leadership – which may in fact have been disguised by the even more blatant ineptitude of the Brexit process – it’s not surprising that few people are enthusiastic about voting Conservative. But the other parties are not faring well, either. Labour is at least as divided over the EU as the Tories, and has a host of other woes; a parliamentary party at odds with both their leader and the rank and file of their traditional support, an ongoing failure to tackle institutional anti-semitism, entryism of the sort which destroyed their electoral credibility in the 1980s and, above all, Jeremy Corbyn.

It takes some doing for an Opposition leader not to be crushing a government as dreadful as this one, but he has managed it. Labour may have just

pulled ahead in the most recent polls, but Mr Corbyn’s approval rating, at minus 47, is even worse than Theresa May’s (-43).

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Meanwhile, the Liberal Democrats, who by any normal logic ought to be hoovering up most of the 48% of the electorate who voted to remain (at least in England and Wales), are nowhere to be seen. Far from storming to power, they have just been overtaken in the polls by Ukip, back again despite the fact that its raison d’etre ought to have vanished. Indeed, thanks to the abject failure of Mrs May’s Brexit strategy, back again twice over, since we also have the Brexit Party, launched by Nigel Farage with the ominous, if hilarious, slogan “No More Mr

Nice Guy”.

Since no one, least of all their leaders, seems to know what most of the parties actually believe in any more, this strange duplication is in evidence on the Remain side as well. Can anyone, for example, yet identify the policies that differentiate Change UK or Renew from the Liberal Democrats? Or, indeed, predict whether they will attract more disenchanted Conservative or disillusioned

Labour voters?

The SNP, having a fairly coherent position on Brexit, can be expected to gain in electoral terms from the confusion and division in other parties, but that may only offset the decline in support which all parties experience after they have been in government for a significant period. And while opposing Brexit may, for now, provide a useful rallying point, it’s less obvious that the issues it brings to the fore are helpful

for the party’s long-term aims. The

poll commissioned by Progress Scotland, which suggests only 30

per cent now back independence, indicates that at least some of the

SNP’s support in Holyrood and Westminster elections would not translate to a majority in any future independence referendum.

The basis on which the parties traditionally divided may no longer be the chief interests of the electorate; the trouble with a big issue, such as independence – whether it’s UK independence from the EU or Scottish independence from the rest of the UK – is that both its supporters and opponents begin to see all other issues through that lens. Yet support for independence shouldn’t necessarily imply, say, a Centre-Left position on economic matters, nor does support

for Brexit automatically indicate a

desire for a more free-market position on trade – as Mr Corbyn’s stance demonstrates.

The most depressing thing about

the current political climate, apart from the shoddy quality of the majority of politicians in all parties, is that it is difficult to see any obvious way in

which a realignment of UK politics

can be brought about, especially if, as

I suspect, the assumed preference of the voters for a moderate, centrist party seldom manifests itself in electoral terms. The fate of the Alliance and the SDP, and the position of the LibDems now, tends to reinforce that inconvenient contradiction.

Instead, people seem simply to desert the polling station altogether, or transfer their allegiance to an ever-expanding list of marginal or nakedly populist parties (which are themselves particularly prone to splintering and factionalism).

And so, at the very moment we could do with some unifying, energetic political solution to the chaos, huge chunks of the electorate either become detached from mainstream politics altogether, or embrace fringe movements. The tragedy of help is that

it never arrives.