A poll the other day revealed that more than nine out of ten members of Momentum, the pro-Corbyn “party within a party” in Labour, believe that anti-Semitism was “wildly exaggerated” by those who wish the party ill. Even if one discounts Momentum members as the most extreme members of Labour – those who supported Chris Williamson and Ken Livingstone right up to their suspensions from the party, and in some cases beyond – it is salutary to learn that even amongst “normal” Labour members, 73 per cent happily believe that anti-Semitism was “wildly exaggerated by right-wing media and opponents of Jeremy Corbyn”.