I cannot recall any Jews being particularly shaken by the familiar French Canadian ritual of throwing stones at synagogues when I was growing up in Montreal’s multiethnic Outremont neighborhood in the late 1950s and early ’60s. Not only was it a common occurrence that garnered no press attention; it was in fact a bit of a game, immortalized by writers like the novelist Mordecai Richler and poet Irving Layton. Another such game was the Quebecois kids’ ritual of throwing snowballs at “les maudits Juifs” (the very first French words I learned as a young child) walking to and from synagogues and yeshivas.While we never dared retaliate against the stunning stained glass of the town’s ubiquitous Catholic churches, vigorous snowball battles between Jewish and French kids (often with rocks embedded in the snow) were an almost daily activity in the wintertime. I recall this warfare rather fondly, as I do many more unhealthy aspects of growing up in a charged and diverse environment in the days before “diversity” became an abstract social ideal.We kids did not shake; we fought back. And the shattering of glass did not evoke Kristallnacht to the many equally unshaken Holocaust survivors then living in Outremont. The most frequently targeted shuls simply installed wired window shields. Problem solved.How different has been the worried response to this weekend’s attacks on four synagogues and a yeshiva in Montreal’s most heavily Jewish-populated township, Cote St. Luc. The vandalism, which left a number of windows shattered but no one hurt and no Torah scrolls or sacred books damaged, led the evening news on both of Montreal’s English television stations. “Montreal Jews Shaken After Four Synagogues, School Vandalized” read the headlines in Monday’s Montreal Gazette. The story also led the Sunday evening news on Canada’s national CTV network.One might credit this sudden flood of attention to the prevailing ethic of political correctness, in which slurs and petty hate crimes that were once accepted as part of life in the big city are now taken with the utmost seriousness. After all, the very idea of creating a separate, more seriously punishable, criminal category for “hate-based crimes” only emerged in the 1980s, in both Canada and the United States.Yet the real reason the recent spate of attacks on Montreal’s Jewish institutions—as well as some recent physical assaults on Hasidic Jews in Outremont—is newsworthy is that ethnic violence is no longer local, and the perpetrators (those who have been apprehended to date) are not Quebecois street toughs. After the firebombing of the United Talmud Torah in the Montreal suburb of Ville St. Laurent in 2004, the nasty work of North African Muslim immigrants, the Jews of Montreal came to a painful realization that they were no longer dealing with rock-filled snowballs. Today’s attacks are not a continuation of the lame local games we used to play. They are something new, and more frightening.The Montreal Chamber of Commerce has long showcased the city as a taste of Europe within driving distance of New York and Boston, which it is. But, along with the sweetness of old Europe, Montrealers have been tasting the ugliness of the new Europe’s serious violence and racial tensions, generated by a rapidly growing underclass of Muslim immigrants.Unlike American states, as well as Canada’s other nine provinces, Quebec enjoys complete autonomy in the domain of immigration policy—and has long given priority to immigrants from former French colonies such as Haiti and Vietnam. Today, the largest numbers of French speakers come from former colonies in Arab lands from Morocco to Lebanon. The city of Montreal today has the world’s largest Lebanese community outside of Beirut and the second-largest Moroccan and Algerian diasporas, after Paris and Marseilles. As in France itself, these immigrants have brought a deep, historically rooted contempt for European cosmopolitanism and heavy doses of anti-Semitism. Those apprehended by the Montreal police and the Royal Canadian Mounted Police for involvement in the dozen or so attacks on Jewish institutions in the city during the past five years—which included the fire-bombings of a synagogue and a Jewish day school—were all Quebeckers of North African descent. None were native French Quebecois.How the city’s Jewish community, already severely depleted by the mass exodus that followed the rise to power of the separatist Parti Quebecois, fares remains to be seen. But one thing is certain: Attacks on Jewish institutions such as those of last weekend are part of a grave international problem. And Montreal is increasingly becoming a lure for those who dream of more spectacular—and potentially devastating—acts of terror.Allan Nadler, a professor of religious studies and director of the program in Jewish Studies at Drew University, is currently a visiting professor of Jewish Studies at McGill University in Montreal, Canada.