Nothing better illustrates the Labour Party’s attitude to antisemitism than its reaction to John Ware’s BBC Panorama investigation.

Instead of attempting to deal seriously with the revelations from eight former senior staffers, it first tried to scare the whistleblowers into withdrawing their statements by sending them  legal letters; then — when they stood firm — dismissed them as politically motivated.

On Tuesday, three Labour peers resigned the whip over antisemitism. Again, Labour’s response was not to attempt to engage with the issue but to attack the peers, calling them “offensive”.

The evidence is, of course, overwhelming that Labour is institutionally antisemitic. Should anyone doubt this, they need only look at how Labour deals with those who bring forward that evidence.

A party that was serious about tackling antisemitism within its ranks would welcome help. A party that chose to remain antisemitic would leave the antisemites in place and attack those who attempted to deal with them. In other words, it would behave exactly as Labour has behaved.

Which brings us, again, to the question of those Labour members who are not antisemitic.

It was, once, credible to argue that the best response was to stay and fight. That time has long passed.

We could face an election imminently. By campaigning for a Labour government, members are campaigning to put hard-core racists into power. There is no ambiguity about this and no escaping it.

No anti-racist can in good conscience remain in a party which is led by an antisemite who surrounds himself with Jew-haters, let alone aim to put these people in power.