Photo by Christopher Furlong/Getty Images. Keir Starmer has sought to define his Labour leadership through “zero tolerance” of anti-Semitism. But when it emerged on Saturday night that the party’s Rochdale by-election candidate Azhar Ali had expressed an anti-Semitic conspiracy theory – that Israel allowed the 7 October massacre to happen to give it a “green light” to invade Gaza – Labour stood by him. Earlier today, shadow cabinet minister Nick Thomas-Symonds, a close ally of Keir Starmer, said that Ali had “fallen for an online conspiracy theory” and that his apology was sufficient. Yesterday shadow international development secretary Lisa Nandy...