Never less than up-to-the-minute, I have just read Boris Johnson’s 2004 novel Seventy Two Virgins. If you’re wondering if that title doubles as a description of its readership, you’re on the wrong track. It sold well, and the reader is duly lured in with the cover quote, promising “Johnson scores in his comic handling of these sensitive issues”.

Mm. For some of us, Boris’s reputation as a dazzling writer is very emperor’s new prose. But he is certainly better suited to fictions than facts. The most majestic thing I read this week was a review of Johnson’s Churchill biography by the eminent historian Richard Evans, which contains such affectless drive-bys as: “The Germans did not capture Stalingrad, though this book claims they did.” Bodybag for Mr Johnson, please.

That said, a lot of psychology does fall into place when you discover that in Seventy Two Virgins, Boris’s hot 23-year-old female character is a) called Cameron and b) regards a certain type of posturing verbosity as the ultimate knee-trembler. Or as the author puts it: “Cameron had a deep and sexist reverence for men who really knew stuff. It amazed her how little appearances really mattered.” I bet it did. Still want more? Tough; because you’re getting it. “If that man’s disquisition had enough interest, fluency and authority, it would speak directly to her groin.”

Ooh Boris, can you quote Thucydides while opening a kiddie daycare centre again? Can you do the speech about selling tea to China and French knickers to France for the 900th time? Can you say “mugwump” like it’s the Manchurian trigger word for activating the most abandoned form of female sexuality? Come on, don’t stop now, we’re all ALMOST THERE.

Well, sorry, sex hounds – but not today. The recovering foreign secretary needs to laugh at women in niqabs in order to stiffen up his new base. Don’t worry – the product all comes in discreet packaging.

As you will doubtless be aware, Boris used his Telegraph column this week to joke that women who wear the burqa – he meant the niqab but whatevs – look like “letterboxes” and “bank robbers”. These gags have now been described as “pretty good” by Johnny English star Rowan Atkinson, though I think I’ll wait for late-era John Cleese to praise them before I make my mind up.

Either way, I am amused (though not surprised) to discover that the hijab-wearing Remona Aly once wrote a satirical Guardian column suggesting different uses for the burqa. But I am even more amused at the suggestion that this is precisely the same as a senior politician making fun of women who wear the garment in order to advance his leadership ambitions. It is, as Spinal Tap’s David St Hubbins once remarked, such a fine line between stupid and clever.

That said, the furore has inspired various valuable public services. A 2013 clip from Question Time was resurrected, in which Emily Thornberry explains she wouldn’t want her child looked after by someone wearing a burqa. A reminder that, while it may currently suit some people to forget Thornberry’s essential snootiness about all manner of things, they’re not going to be able to ignore it for ever.

As for Atkinson, who has previously made many valuable points about free speech, I’m sorry he can’t see that punching up at Islam is fine, while punching down at the tiny number of women who wear the niqab and are already disproportionately likely to suffer street abuse is something else. It’s the equivalent of that classic footage of Boris flattening the 10-year-old Japanese kid while playing rugby on a trip to Tokyo. You show him, big guy! Second toughest in F block.

Of course, absolutely none of this is really a freedom of speech issue. It is one of the cast-iron rules of modern political discourse that if someone tells you that you can’t say a certain thing any more, they will use their next breath to say that very thing. Every time. “You can’t say this any more, but Muslim women make me feel uncomfortable”; “I know you’re not allowed to say this any more, but these are Jewish mind games.” I mean … you patently can effing say it, can’t you, because you literally just have.

Still, it’s instructive to see who rides to whose defence. One of the other great rules of the modern era for a certain stripe of populist is that you don’t punch right. (Or, in the case of Jeremy Corbyn, you don’t punch left.) You need those guys. So Donald Trump tells Infowars wingnut Alex Jones that his show’s “amazing”; and that hammy old fraud Jacob Rees-Mogg isn’t about to ask for a bit more civility from Johnson.

Instead, the North East Somerset MP declared Boris “completely entitled to say it”. To which the only response can be: is this the same Rees-Mogg who is against even raped girls committing the “second wrong” of abortion – but who snowflakily accused the BBC of “straying into religious bigotry” for asking about views such as this? Like I say, it’s such a fine line between stupid and clever. (A friend who had to sit through many of Rees-Mogg’s debating society performances at Eton memorably described him to me as “like a posh Karl Pilkington”.)

So here we are, with the Tories and Labour still pretty much neck-and-neck in the polls, just as they were a year ago – each unable to pull ahead against what they’ve decided are the worst bunch in modern history. It is easy, in the cliched Punch-and-Judy world of Westminster, to sigh knowingly at the pendulum swing. Last week we were on Labour’s latest grim paroxysm of antisemitism; this week it’s the Tories and Islamophobia.

And yet, if we take a step back, doesn’t the picture resolve into something that should be much more worrying? It turns out we are now a country where both major parties are locked in sustained, self-started fights with minority communities. That feels ominous. We are still only in the phoney war of Brexit, after all – the period where the questions are all about who benefits. Who benefited from what even some Brexit voters such as Danny Dyer have decided is turning pear-shaped? Was it Arron Banks? Is it Johnson? Will it be Gove?

If much of history is any guide, we might reasonably fear that once the realities kick in, another phase will follow the period of asking who benefits. And that will be the period where people decide who gets blamed. Who is at the sharp end when things don’t turn out how they were promised? Who is turned against? Who gets it in the neck? It certainly isn’t well-off and socially insulated politicians, however much of a metaphorical pasting they might imagine they take for things that are, after all, their own fault. The weak will suffer. In this context, it is more than a grim symmetry to find significant factions in both major political parties pitting themselves against minority communities. It is an alarm bell.

• Marina Hyde is a Guardian columnist