An ugliness we should never have seen again.

The world’s oldest hatred is also one of its most inexplicably persistent. An episode of Family Guy flashes back to Ancient Egypt: toiling to build the pyramids, one Hebrew slave says to another, “They say all peoples must go through some hard times. Well, we Jews are getting ours out of the way early. From here on out, it’s going to be nothing but smooth sailing”. The Simpsons earlier made a similarly black joke.

Because the grim truth is that the history of the Jews has been one of almost constant persecution. After the horrors of the Holocaust, it seemed that at last the West at least, had largely learned its lesson. But anti-Semitism is making a shocking comeback. Europe’s Jews are fleeing again and even in supposed havens like America and Australia, anti-Semitic attacks are rising.

Some of this can be sheeted home to increasing Islamic immigration. “Anti-Jewish sentiment is endemic in the Muslim world” according to the Pew Research Center. In Australia, Muslims are over 25 times more likely to perpetrate an anti-Semitic incident than anyone else. Sydney’s Jewish heartland, Bondi, refused permission for a new synagogue on the grounds that it was too risky a target.

But what is perhaps most disturbing about the resurgence of anti-Semitism is that it is so predominantly a left-wing phenomenon. Whatever their faults, for a very long time the moderate left and even the communists (despite the Stalinists’ campaigns of anti-Jewish persecution) were a haven for Jews.

Not any more.

Anti-Semitism is fast becoming de rigeur in the mainstream left. For the moment, left-wing anti-Semitism still tries to hide behind a veneer of respectability by trying to pretend that it’s just “anti-Zionism”, or criticism of Israel. But this threadbare excuse is wearing thin to the point of transparency.

In Britain, the mask is almost completely torn away. Journalist Ben Cohen describes UK Labour as “institutionally anti-Semitic”. Its leader openly sympathises with anti-Jewish terrorist organisations and hand-waves away anti-Semitic outbursts. Jewish Labour MPs need bodyguards to protect them against members of their own party. Prominent lawyer Mark Lewis says that “Jeremy Corbyn moved the rock, and the anti-Semites crawled out…they’re not going back”.

The United States isn’t much better. Of the Democrats’ rising stars – many of them Muslim – have an odious track-record of anti-Semitism. Possibly the most overtly anti-Semitic Democrat star politician is Somali-born Ilhan Omar, who regularly posts ugly, “Protocols of the Elders of Zion”-style conspiracy theories about Jews controlling the world.

Despite all this, many Jews cling to the left’s skirts, even as many black Americans, another group traditionally rusted on to the left, “walk away” from the Democrats. Although the Democrats still command the lion’s share of the black vote, their grip is slipping. Even by the early 2000s, political analyst David Bositis was noticing “a fairly long-term pattern of decreasing identification with the Democrats by younger African Americans”.

But, in a way, it’s hardly surprising that Jewish voters, despite the rise of conservative Jewish firebrands like Ben Shapiro, should cling to the devil they know. The media, overwhelmingly left-wing, incessantly downplay anti-Semitism on the left and in Islam. When an Islamic terrorist attacked a French kosher supermarket in conjunction with the Charlie Hebdo massacre, media bent over backwards to not only obscure the attacker’s Islamic identity but avoid any mention at all of the victims’ Jewishness.

None of this lets the right off the hook, though. If the political right think they can point fingers at the left, they need to think again.

Anti-Semitism has long been assumed to be a beast peculiar to the political right, and not without reason. But, whatever the historical reality, the modern fringe right has adopted anti-Semitism with unholy enthusiasm. Anti-Semitism is almost canonical on the alt-right. Their most odious excrescence, perhaps, was the tiny cabal of swivel-eyed loons gibbering “the Jews will not replace us!” in Charlottesville.

Right-wing social media is disturbingly rife with Jew-hating. Free speech network Gab is the whipping-boy for online right-wing anti-Semitism. Although a quantitative survey showed that Gab’s users trend heavily to the centre-right, the same survey showed that the very small fringe of far-rightists on Gab are disproportionately vocal (making Gab almost the mirror-image of Twitter, which is dominated by a hyper-vocal minority of far-leftists). Unfair as it may be, Gab was tainted by association with the Tree of Life synagogue shooting.

The mainstream right might be tempted to assume an air of smug superiority as the left is engulfed by a septic tide of anti-Semitism, but they must first cast out the beam in their own eye. Denial is as bad as complicity. The time is long past for the right to put its own house in order.

Punk rock philosopher. Liberalist contrarian. Grumpy old bastard. I grew up in a generational-Labor-voting family. I kept the faith long after the political left had abandoned it. In the last decade...