IN ONE Jewish school in London, pupils drill for a possible terrorist attack. A synagogue has cancelled a children’s trip to Disneyland in France. Police and community groups have stepped up patrols in Jewish areas. After the murderous attack on a kosher supermarket in Paris on January 9th, British Jews are scared. Should they be?

Jews worried even before the killings. In a study of British Jews last year by the Institute for Jewish Policy Research (JPR), almost 70% said that they felt anti-Semitism had increased in the past five years. Considering the atrocities in Paris, it should come as no surprise that many Jews feel uneasy in a way that they have not for some time, says Ephraim Mirvis, Britain’s chief rabbi. But he cautions against alarmism. Indeed: though some statistics suggest otherwise, anti-Semitism is not rising.

Research last year from the Pew Global Attitudes survey suggests that just 7% of Britons harbour unfavourable views of Jews. That is a little less than in France and much lower than in Italy or Greece, where the rates are 24% and 47% respectively. The figure in Britain has been fairly stable—hovering between 7% and 9%—for a decade, points out Daniel Staetsky of JPR. Levels of prejudice against Muslims are higher in Britain, as in other European countries.

The Community Security Trust (CST), a charity that monitors anti-Semitic incidents, reckons that there were 529 in 2013, the lowest tally since 2005. None involved grievous violence. But the outfit reckons that there was an uptick in 2014. The first half of the year saw a 36% increase on 2013. Last July the CST recorded 302 incidents, its highest ever monthly total. London’s Metropolitan Police say the numbers of hate crimes against Jews reported last year almost doubled, though they remain low.

That has much to do with events elsewhere in the world. Anti-Semitic incidents tend to track violence in the Middle East. A sharp rise in 2009 coincided with Israel’s assault on the Gaza Strip. A rise in 2014 would coincide with Israel’s summer incursion into Gaza. Criticism of Israel is not the same as anti-Semitism, and the CST is careful to distinguish between the two. But, the organisation points out, the former can be used to bash Jews more generally.

The CST also notes that many incidents occur around the Jewish high holy days, when more people are going to and from synagogues. In 2013 incidents most commonly involved public verbal abuse hurled at visibly Jewish people, including shouts of “Heil Hitler” and “fucking Jewish bastards”. Changes in the demography of British Jews may exacerbate this. The haredi, or ultra-Orthodox, are a growing proportion of British Jews. Their clothes mark them out clearly as Jewish, as do the schools they attend and the areas where they live. As their numbers swell, abuse could increase, even as anti-Semitism more generally does not budge.