(CNN) -- On Sunday, there was a rally in London to protest something I never thought would need protesting in modern Britain: the rise of anti-Semitism. The rally was in reaction to a series of strange, unsettling incidents that took place during the recent demonstrations against Israeli military actions in Gaza. In one case, the manager of a supermarket in London decided to take all the kosher food off the shelves. He apparently feared that demonstrators outside might trash the shop; one member of the staff reportedly said, "We support free Gaza." The supermarket chain called it "an isolated decision ... in a very challenging situation."
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Tim Stanley: Anti-Semitism surfaced in the wake of the controversy over Gaza war
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He says some conflate Israel and its policies with Jews in general
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It's vital to ensure that historic prejudice doesn't get revived, he says
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Stanley: Anti-Semitism has long been connected to far right, but some on left tolerate it
But while that might explain fury at the Israeli state, it does not explain attacks on @placeholder overseas.