Like Kent in King Lear or, if you prefer, Jim Morrison singing over the opening of Apocalypse Now, many of us now wonder if this is the promised end, or merely the image of that horror. Or – which may be even more depressing – asking: is there no end to this madness?

As the writer Damian Thompson pointed out in his study of apocalyptic belief, the measurement of time is inextricably bound up with the supernatural. One aspect of the theological view is that while the end for each of us (death) is final, what follows, good or bad, is endless.

Politicians are big on ends, though all the evidence is that Enoch Powell was right when he maintained that “all political lives, unless they are cut off in midstream at a happy juncture, end in failure”. The reason is that politicians are usually talking about ends as specific objectives, but conflate the achievement of those ends with the ultimate; as if it will usher in the Kingdom of Heaven, or at least solve a problem. And practically no political measure, even if triumphantly concluded – that is, implemented – ends anything definitively.

A notable theological expression of this – Jesus’s statement that “Ye have the poor always with you” – is an echo of Deuteronomy 15:11’s “For the poor shall never cease out of the land”. That’s not, as it’s sometimes presented, an argument for complacency or a gospel of despair; the Old Testament verse immediately continues with a commandment to help the poor, but it is an acknowledgement that human efforts and solutions always fall short of perfection.

An inability to see the difference between the end as an aim or political ambition and as a conclusion is at the heart of Brexit, and the conundrum for whichever hapless politician has to take it on. The argument is not so much about whether no deal can be ruled out – neither sensible in negotiating terms, not possible in practical ones, since it’s the default – but about the notion, now firmly planted in the minds of many Leavers, that it would settle anything.

It won’t, and that will be true whether you think it would be an economic disaster or provides, in the long term, the best opportunities for success. Either way, the first thing that will follow a no-deal Brexit on October 31, if that’s where we end up, will be yet more negotiations, and probably very urgent ones, in which we’re less likely to have a strong hand.

They won’t all be with the EU; joining CANZUK or the Cairns Group, setting up a Commonwealth FTA or other bilateral trade deals will all be likely aims; some may or may not be easier once we’ve left. But the point is that leaving will not be the end, or the beginning of the end; it won’t even be the end of the beginning.

Despite this, the Brexit Party, which advocates no deal as the preferred option, is now leading the polls, while most of the Tory membership (who haven’t absconded to the Brexit Party) and even many Labour voters also take that view. It’s a natural consequence of the abject failure of Theresa May’s attempts to deliver Brexit, but an illogical one; it confuses the end of our membership of the EU, which might have been reached in dozens of different ways, with a solution that ties up the political and economic issues raised by it, as if the act of leaving were a conclusion. Consequently, people who held up Norway, for example, as a model, now argue that a similar solution would be a betrayal.

In this, Brexit closely resembles the independence debate. There used to be a great many differing views but, since the referendum, those on both sides have tended to polarise, to harden their opinions and to express them more intemperately. This seems to be true whether you back independence and oppose Brexit, or the other way round, or support or oppose both.

Hence the extraordinary and often inconsistent gymnastics on the nature of each kind of union, wishful thinking about what membership or independence would deliver, unfounded optimism about the popular will and further votes (always giving the result you favour), economic utopianism, or predictions of meltdown.

It’s not that there is no case for independence, or for Brexit, or for any possible combination of the options. It’s merely that to see either as a final settlement of the issue is true in only a limited way. Yes, we’d have voted to be out (of whichever one it is you’re talking about). But does anyone think, after the experience of the past three years, that separating the component parts of the UK would not involve the same kinds of political challenges – which many would no doubt call obstructions of the democratic will – economic upheavals, bad temper in public discourse and demands to rerun the vote that have characterised Brexit, and for all we know, may continue for years to come?

Anyway, achieving the end of formally getting out of either arrangement would, as I say, not be the end, but the start. Even if you dismiss either of the “Project Fear” approaches before both referendums – proved wrong for Brexit’s immediate impact, as yet unknown if we actually leave; and, in the case of the independence vote, which we’ll never know, since it didn’t happen – a bumpy ride is almost certain to follow.

Big, closely-contested questions of this sort are not in the ordinary run of political issues, nor do they end, even if you can get to the point of obtaining a majority and legislating for them. Meanwhile, piffling issues like schools, welfare, hospitals and housing get swept aside by a millenarian vision of paradise or apocalypse.

No-one doubts that there’s a desire to get these questions over and done with, and back to normal politics. But it won’t happen. It can’t happen while any sizeable number (probably around 40 per cent or more) passionately want the opposite of what is favoured by the rest of the population. And while the idea of getting to the end pushes more and more people to the extremes of the argument, as if only the poles were a viable destination. In politics, everything that doesn’t end is bound to end badly.