One of Britain’s best-loved MPs — Frank Field — has quit the Labour Party in protest at the anti-Semitic and increasingly vicious direction it has taken under its hard-left leader Jeremy Corbyn.

This is a depressing symptom of a rapidly escalating problem across Western culture.

The anti-Semitism is, of course, horrifying. For those of us who grew up in the shadow of the Holocaust, it seems almost incomprehensible that the Britain which did so much to beat Hitler has become a Britain where Her Majesty’s Opposition party is so flagrantly, shamelessly anti-Semitic that British Jews are making plans to flee the country if Corbyn ever gets voted into power.

But equally shocking and significant, I think, is the second reason Field gives for leaving.

Here he is writing in the Liverpool Echo about the problems within his own constituency:

Birkenhead is a case in point of how the Labour Party has been overrun by individuals who demonstrate intolerance of, and nastiness towards, those who hold different views to their own. I have attempted, over the past eighteen months, to get the national Party to take seriously the sheer thuggery and blatant bullying that now characterise Birkenhead Constituency Labour Party. Not one of my submissions has ever been investigated fully or produced a report. This intolerance is often racist, ageist and sexist in nature. Again most recently, a woman member campaigning for the Party was reduced to tears by the rage that engulfed her from a male councillor. There have been many other such incidents, now too numerous to list.

Yes.

And this isn’t a problem peculiar to Field’s local party branch. It’s everywhere, in the U.S. as much in Britain. The forces of the left have got significantly, noticeably, painfully nastier. At the risk of sounding like them, I’m going to use a term they use far too freely themselves: the left has become fascistic.

You can see this in the increasing aggression and intolerance of left-wing activist groups — such as Occupy, Antifa, Black Lives Matter, and Momentum. They’ve become so shameless, so self-righteous they’ve stopped even pretending they consider violence a bad thing. As long as the person you “punch” is a “Nazi” — basically, anyone even slightly to the right of Stalin — then apparently it’s entirely justified.

I talk about this on my podcast with Dick Delingpole.

The violence is fuelled by another thing the new left is always banging on about: rhetoric.

Look at the social media account of any prominent or vocal leftist and there’s a vaunting ugliness, a shrillness, a determination to smear the opposition which goes far beyond the normal rough-and-tumble of political debate.

By “normal”, I mean the standards that prevailed until maybe ten years ago — in the days when, sure, you disagreed with your political opponents but never to the point of wishing them actual harm.

Those innocent days are over.

It suits the left’s narrative to justify its own violence by claiming that it is only acting in response to violence from the right. (Or “alt-right”/”Nazis”/”fascists”/etc.) This is why leftists made such a big deal of Charlottesville — an event whose details they have rewritten so that it looks as if all the violence was on the one side, and all the goodness and innocence on the other.

One thing that hasn’t changed about the hard left is their absolute disregard for facts: remember, for example, how for decades — and against all evidence to the contrary — the Soviet communists persisted in blaming the Katyn massacre of mostly upper-class Polish officers on “Nazis”.

The ugliness, the mendacity, the violence are all things you associate with totalitarian movements — and whether you call them communist, socialist, or fascist they’re all manifestations of the same controlling, hate-ridden, illiberal impulse.

And these days they are a problem you encounter almost wholly on the left, not the right.

So you can see why an old school, Christian, Labour Party man like Frank Field might be perturbed by the left’s apparently unstoppable move towards violent extremism.

We all are.