The UK Chief Rabbi Ephraim Mirvis’s excoriating article in Monday’s Times has ripped open the wound that is Labour’s anti-Semitism problem. Mirvis highlights the "anxiety" among British Jews; he decries Jeremy Corbyn’s complicity in anti-Jewish prejudice, and denounces the Labour leadership’s "utterly inadequate" response to anti-Semitism.

Attuned to the everyday racism suffered by people of color, to Islamophobia, and to the legacies of colonialism, Labour has failed to comprehend and deal with the racism in its own ranks directed at Jews. This is an extraordinary outcome for a party which is, with good reason, proud of its legislative record on equality, race and discrimination.

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The Chief Rabbi is surely correct to point to Labour’s want of effective leadership. But the issues which Labour faces go deeper than this. The very problem itself has been misconceived - both by the party leadership and its critics.

Amidst the claim and counter-claim over anti-Semitism in Labour there are two points of consensus. One is that prejudice against Jews is "a virus" (or sometimes a "disease," a "cancer" or, for Chief Rabbi Mirvis, a "poison") that erupts or takes root at different times and infects people who were once healthy. It follows from these metaphors that anti-Semitism can be "expelled" or "stamped out" from the Labour Party. The second point of agreement is that counting anti-Semites is the key measure of the party’s problem.

The quarrel only begins at the next stage: when we ask whether anti-Semites are the many or the few within Labour, and whether Jeremy Corbyn is one of them.

The idea that anti-Semitism is a virus or a poison has become a cliché. Some clichés express important truths, but this one obscures far more than it reveals.

In Britain prejudice against Jews has been longstanding and widespread, not discontinuous. For the most part the problem we face today is not ideological anti-Semitism displayed by a few, but negative and stereotypical ideas about Jews that have accumulated over centuries and are embedded deeply within our culture.

Rather than conceive anti-Semitism as a virus, we will do better to think of it as a deep reservoir of stereotypes and narratives, one which is replenished over time and that can be dipped into with ease.

This is the nub of Labour’s problem. And it has been overlooked both by the party and its critics. To understand why, we need to consider some stark facts.

The number of thorough-going, ideologically committed anti-Semites in Britain amount to a tiny minority within the adult population. In 2017, Jewish Policy Research (JPR) estimated that 2.4 percent of British adults combine open dislike of Jews with developed negative ideas about them.

But the number of anti-Semites is not the same thing as the presence of anti-Semitic ideas. According to JPR, 30 per cent of British adults assent to one or two anti-Semitic attitudes. For example, these people will endorse the idea that Jews think they are better than other people or that they get rich at the expense of others or that Jews have too much power in Britain.

So, in contrast to the small number of anti-Semites in the country, the diffusion of anti-Semitic attitudes reaches almost a third of the population.

Another survey, by YouGov, demonstrates these sorts of attitudes towards Jews arise more frequently among Conservative voters (40 percent) and on the right of the political spectrum than among Labour voters (32 percent.) Why, then, is there so much talk about anti-Semitism in Labour?

The mistaken and much-repeated idea that Labour’s crisis is a smear perpetrated by political opponents who want to undermine Jeremy Corbyn is one attempt to address this puzzle. According to yet another poll, this explanation appeals to a majority of Labour members. It is an idea which echoes the argument provided by Labour’s leaders and outriders, and was vividly illustrated by Corbyn-supporting social media posts in the wake of Chief Rabbi Mirvis’ article.

The party’s formal response to the Chief Rabbi, characteristically, tried to bring the issue back to numbers and tacitly endorsed the idea that accusations of anti-Semitism are overblown and disproportionate. The party insisted that anti-Semitism complaints amount to less than 0.1 percent of the party’s membership.

This script falls back on the old idea that anti-Semitism is a virus that latches on to Labour but which, fortunately, has infected only a few members who, once identified, can be kicked out.

This argument is wildly implausible.

First, it flies in the face of all the survey evidence we have mentioned. We can add to this the work being undertaken by Hope not Hate. Earlier this year, the anti-racist advocacy group identified 27,000 UK-based left-wing Twitter accounts that either directly spread anti-Semitic ideas or deny and trivialize anti-Semitism.

Assessing this sort of material, it is often hard to distinguish between Labour members, Labour supporters and the wider penumbra of Left opinion. But it is safe to say there is a political culture on the left that draws on anti-Semitic ideas.

The question we need to ask is not whether there is a problem of anti-Semitism in the Labour Party, but why the anti-Semitism that exists within Labour rises to the surface. Why is anti-Semitism a problem for Labour when the Conservatives are, on the face of it more vulnerable to anti-Jewish sentiment?

This is where the distinction between ideologically-committed anti-Semites and a more diffuse anti-Semitism that subsists in our political culture will help. For the most part, Labour, and the left more broadly, don’t talk about Jews because they are committed ideological anti-Semites, but because they associate Jews with some of the key issues they most care about: the legacy of colonialism and the operation of power within capitalist society.

In the case of colonialism, this happens because they regard Israel - the Jewish state - and the continuing injustices suffered by Palestinians as an expression of colonialism.

Open gallery view Campaign Against Anti-Semitism demonstration outside the head office of the British opposition Labour Party in central London. April 8, 2018. Credit: TOLGA AKMEN / AFP

In the case of capitalism, the connection is less direct. Some on the left understand economic and political power as a set of overlapping conspiracies. This line of thought will always make its disciples vulnerable to the widely-held idea that Jews exert a powerful, covert and malign influence in the world’s affairs.

Once Jews are conceived as a problem, there is a reservoir of negative stereotypes and narratives available for use. People draw on this pool for its apparent explanatory power. It provides a simple and, to some, a compelling explanation for people in search of just that.

In Britain today this is most visible on the left. One hundred years ago, it was commonplace among Conservatives, who used similar ideas about Jewish power and conspiracy to explain the Bolshevik revolution in Russia and the threat posed by Communism. We see traces of similar ideas within the political right today when people blame Soros and other "cosmopolitans" for blocking Brexit.

For as long as we think the problem we face is one of anti-Semites and not as one of anti-Semitism we will misdiagnose it. The "virus" metaphor has been one factor - albeit one among several others - that has stood in the way of Labour facing up to its problem.

Jewish leaders and their allies habitually reach for the "virus" or "poison" metaphor, and this prevents them from calling Labour to account more effectively. When Labour leaders and supporters say there are few anti-Semites in the party, they are right. But this leads them to imagine mistakenly that they can address anti-Semitism by ejecting "a few bad apples."

The reality is that Labour’s anti-Semitism problem is neither so simple nor contained: the issue is one of anti-Semitism, not anti-Semites. This is something that will only be addressed by education, contrition and a leadership able to recognize and explain to members how racism can enter a political party, even one that conceives itself as the embodiment of anti-racist principles.

David Feldman is Director of the Pears Institute for the study of Antisemitism at Birkbeck, University of London where he is also a Professor of History. He was a Vice Chair of the Chakrabarti Inquiry into Antisemitism and other forms of racism in the British Labour Party