Baruch Goldstein was an Israeli terrorist who shot dead 29 Muslims, and wounded another 125, in what became known as the “Cave of the Patriarchs” massacre in Hebron.  A plaque by his graveside reads: “to the holy Baruch Goldstein, who gave his life for the Jewish people, the Torah and the nation of Israel.”   Six years after the atrocity, Jewish extremists gathered at his graveside to celebrate the murders.

Now imagine for a moment that Theresa May had visited the site, participated in the occasion, laid a wreath, and joined in a prayer.  You see?  The effort of doing so strains credulity.  It is almost impossible to picture so mainstream, sober, and balanced a politician doing anything of the kind.

This imaginary parallel with the real-life event of Jeremy Corbyn visiting the graves and honouring the memory of the PLO perpetrators of the Munich massacre doubtless isn’t exact.  But it is rough and real enough to explain why our journalistic colleagues tend to give stories about Labour anti-semitism more projection than those about Conservative anti-Muslim prejudice (real and imagined).

A fish rots from the head down, it is said. The essence of Corbyn’s story is that he never expected to become his party’s leader.  During his long years on far left of it, he thus felt free to do and say whatever he liked, unburdened by any expectation of executive responsibility.

What he seems to have liked doing best – or at least done unwaveringly – is either line up alongside extremists, terrorists and anti-semities, or turn a blind eye to what they said or did, or both.  And since he hasn’t changed his mind on the issues concerned, Labour can’t get the monkey of his views of its collective back.  The papers pile in again gleefully today as they have been doing for months, to the detriment of the party’s opinion polls ratings.

If the Conservative Party has any collective nous – a conjecture that appears doubtful after the event of the last week – it will drop the Boris Johnson complaint.  The rumpus will then vanish from the headlines.  The Corbyn anti-semitism saga, either way, will continue to seize them.  On second thoughts, it’s not his opinions, in this instance, that are the monkey on Labour’s back.  He is the monkey.