Last summer, as Jeremy Corbyn was gliding serenely towards victory in the Labour leadership election, this newspaper asked him a series of questions about his associations with various antisemites.

We said that we believed we spoke for the vast majority of British Jews in expressing deep foreboding at the prospect of his election as leader, a view that was confirmed the following week by a poll of the community which showed that over 80 per cent were concerned by his contacts, and by such comments as his reference to terrorist groups Hamas and Hizbollah as “our friends”.

Mr Corbyn has now been leader for six months, and the only conclusion that can be drawn is that our fears were justified. Labour now seems to be a party that attracts antisemites like flies to a cesspit.

Barely a week goes by without the identification of a racist party member or allegations of racist behaviour by those involved in the party. And the target of that racism seems always to be Jews.

Last week it was Gerry Downing. This week Vicki Kirby. Before that, it was members of Oxford University Labour Club.

It is true that both Downing and Kirby have had their memberships suspended, and an inquiry set up to probe OULC. But when these were first identified, party officers appeared to have almost no interest — as if the very mention of antisemitism was worthy of little more than a yawn.

It was only when the media tumult — and the uproar from some Labour MPs who have no wish to represent a party that tolerates Jew-haters — became too great to ignore that the party acted.

Beyond that, one has to ask how these people were ever allowed to be party members. They did not hide their views.

Mr Corbyn appears to be genuine in his rejection of antisemitism. And yet for all the fine words that he speaks, the plain fact is that he leads a party that antisemites clearly feel is their natural home. If that does not worry him then — to put it mildly — questions need to be asked.

The Shadow Chancellor, John McDonnell, reportedly wishes to abolish Labour’s Compliance Unit, the body responsible for policing its membership. Permitting the memberships of Downing and Kirby may not represent its finest moment, but should Mr McDonnell’s plan take effect, Labour will be still more of a magnet to racists, with even less scrutiny than today. One has to wonder if that is the point.

Most Labour members are thoroughly decent people who are horrified by all forms of racism. And there are many Labour MPs who lead the fight against antisemitism wherever it resides.

But there is now a cancer in their party and it is getting worse by the day. If Labour is not to lose the last residue of trust from our community, it must recognise and deal with that cancer.