The fact that Jeremy Corbyn once wrote a foreword to a reprint of John Hobson’s Imperialism is, of itself, of little interest. Nor is the fact that Hobson was a thoroughgoing antisemite. It is far from unusual for the ideas of despicable human beings to be worth studying.

What makes the Labour leader’s foreword noteworthy and important is that it is specifically Hobson’s antisemitic ideas that Mr Corbyn singles out for praise and which he describes as “brilliant”. He writes: “What is brilliant, and very controversial at the time, is his [Hobson’s] analysis of the pressures that were hard at work in pushing for a vast national effort, in grabbing new outposts of Empire on distant islands and shores”.

Those “pressures”, according to Hobson, were exerted by the finance houses controlled, as Hobson had it, by Jews. Hobson describes the “men of a single and peculiar race, who have behind them many centuries of financial experience, they are in a unique position to control the policy of nations.” 

Mr Corbyn praises as “correct and prescient” an avowedly and unambiguously antisemitic analysis. There is no debate to be had over this, no other possible explanations.

The Leader of the Labour Party has eulogised a series of specifically antisemitic ideas.

Week after week, more evidence emerges cementing the inescapable conclusion that Jeremy Corbyn is an antisemite. So, once again, we pose this question to mainstream, decent Labour MPs: How can you, in all conscience, work towards making a racist politician Prime Minister?

Those who campaign to put today’s Labour into power are, inescapably, working to put an antisemite into Ten Downing Street.