Out of office, but still hitting the headlines: Boris Johnson has propelled that surprisingly large part of the UK political establishment that is not on holiday into another Johnson-related row. Whether, in his description of women who wear the burqa, the former foreign secretary was (a) deliberately pitching for the Ukip vote, (b) just “being Boris” or (c) failing to find the right words as a journalist up against a deadline, he has managed to do two things. Not only has he unleashed something of the public discussion he called for, he has also seemed to set off a proxy contest for the Conservative party leadership, as a selection of Tory remainers – Dominic Grieve, Anna Soubry – threaten to leave a party led by Johnson.

But his remarks have had another effect, too. The response to what he wrote specifically about the burqa – not calling for the sort of ban introduced in some European countries, but ridiculing the practice of wearing it nonetheless – has illustrated how evenly divided UK opinion currently is on this, as on so much else.

All right, so the Sky Data poll can be questioned, as can most opinion polling, but the results do not seem wildly out of kilter with what you see, read or hear – on phone-ins, for instance, or even on the bus. More people thought that Boris Johnson’s remarks were not racist than thought they were (60% to 33%) – but on the signal issue of whether he should apologise, 48% said he should not, versus 45% who said he should.

It is a split similar to the 52%-48% split in the Brexit vote. The age breakdown shows a similar pattern, too: roughly 60%-40% of those polled who were between 18 and 34 argued for an apology; from those over 55, the feeling was pretty much the reverse. And Londoners were most likely to say Johnson should apologise, by 51% to 41%.

What this suggests is that the UK is almost evenly divided on key political questions – which also probably helps to explain why the Brexit question and the negotiations with Brussels are proving so problematic for the government; why almost every significant vote in parliament has been so close; why there is still so much emotion on display more than two years after the referendum; and why public opinion on Brexit remains almost as polarised as it was then. The shift hoped for especially by remainers has simply not happened.

A decade earlier, and the majority might have been greater one way; a decade or so later, it might have gone as decisively the opposite way, but right now, taking the country as a whole, we are stuck with two halves (almost).

It is hard to see any short-term remedy for this division, at least in the political sphere. And long-term solutions are hardly satisfactory in a situation where feelings are running high. But waiting it out and letting inevitable generational change produce a new majority, if not a consensus, may be all that can realistically be expected.

But changes in our political process could – should – help, too. At present, we have an adversarial parliamentary democracy with two main parties that are both split down the middle, along similar culture-wars lines as the population. This weakens both parties and keeps essential argument out of the parliamentary arena. What is surely needed is a new set of parties that better reflect the climate in the country and provide for a genuine opposition.

The electoral system only compounds the problem. First past the post (and gerrymandered constituencies) has the effect of pushing minor parties and sections of opinion further to the sidelines than their numbers warrant. This is one reason why the EU referendum result came as such a surprise for so many: people had a vote that actually meant something – and they used it. A vote in safe seats often seems to mean nothing at all.

Would we be where we are, had Ukip – for instance – or the Greens, say, had the number of MPs that corresponded to their national support? Would it not be healthier to include more strands of opinion – and make their representatives take responsibility for the policies they advocate and the words they use? Other countries manage this – Germany, for one – and enjoy a more civilised and representative political debate. Such change will be difficult for the UK, and possible only with time, but the Boris Johnson row demonstrates yet again why it should no longer be put off.

• Mary Dejevsky is a writer and broadcaster