Many years ago, as a young Jewish boy in Paris, and on the verge of becoming an adult in the eyes of Judaism, I sat with my community for Friday night prayers. The Friday night prayers are a time for reflection on the week and a time of joy as the Sabbath is welcomed into our lives. This night was different and on this night, 3 October 1980, my synagogue on Rue Copernic became a terrorist target. It was my first encounter with antisemitism and threw me into an unknown world where such violence was possible. Through the eyes of the 13-year-old boy that I was, I remember the blood, the chaos and the bodies of the dead on the street. Those images have never left me.

And yet I also remember feeling part of a greater picture, one of compassion and one of humanity. Following this tragedy, more than a million people descended on to the streets of Paris to express their shock and horror. The presence of so many was comforting.

But then the tide turned, and compassion and solidarity were replaced by confusion. With a few words the then prime minister, Raymond Barre, changed everything. His words of condolences were marred by a distinction between the Jewish victims that died and the truly "innocent" victims who were not Jewish but simply had the misfortune to be walking past the synagogue at the time of the bomb blast. As a Jew, I immediately understood that, for some, I was not as "innocent" as others.

The tragedy in Toulouse this week has brought these conflicting memories back into my mind. The bloodbath that took place at the entrance of the Jewish school still has the potential to generate not only solidarity and compassion of the kind we have seen in the past few days, but also division, suspicion and hatred. The news continues to unfold as I write, but if a jihadi is indeed responsible, many will see in the identity of the suspect a definite proof of the never-ending antagonism between Jews and Muslims.

In the middle of a heated presidential campaign, politicians and their supporters will inevitably point the finger at the political and religious identity of the killer, questioning the place of Islam and Muslims in the country. Others will no doubt focus on the much publicised "return" of the four bodies in Israel for burial. One can already hear the unspoken question: were these murdered Jews not "French enough" to be buried in France where they lived? I fear a surge of islamophobia and anti-Semitism, raising doubts on the place of both Jews and Arabs in French society.

Yet there is also potential for a real thrust of solidarity and social cohesion on the horizon, because beyond the shared tears the tragedy of Toulouse confronts France with the complex "multiple identities" notion that it has ignored for too long. Let us look again at the picture through that prism. If the news reports are correct, the presumed killer is a French national, a Muslim certainly, but a French citizen. His first victims, more then a week ago, were three French paratroopers. Two of them were Muslims. All of them served in Afghanistan. His victims at the school were Jews, some carrying dual Israeli citizenship. Such is the reality that France will have to face if it seeks to emerge from this tragedy stronger and more united.

Facing the multiple nature of one's identity within the framework of a shared national citizenship is not easy and it has never been. Judaism, many centuries ago, used the image of the flames of candles to illustrate the survival of the Jewish people as well as the difficulty of defining one's identity in a plural world, at the festival of Hanukah. This was a time when not only did Jewish and Greek culture influence each other, but also when Jews feared for their future amid constant antisemitism. For the rabbis, just as the flame needs the oxygen of the outside world to burn and to shine, so do we. Without the oxygen that our relationships with the outside world provide, we cannot survive in any meaningful way. This image was daring, as in fearful times the natural tendency is to retreat behind our own walls. Yet behind the barricades, the flames will soon lack the oxygen they need.

The image of the flame should not be restricted to Judaism. It could, indeed, be used today by any nation currently facing the challenge of pluralism where cultures and traditions often mingle in an atmosphere of fear and violence. Retreating behind the walls of a simple one-dimensional identity is nothing but a trap. The false sense of security it provides will only lead to a desperate lack of oxygen. Jews and Muslims in France today are at a crossroads. The Toulouse tragedy could tempt both communities into retreating behind the boundaries of their respective communities. France as a nation could also be tempted to evade the complex makeup of its diverse population, seeking refuge behind an illusory French traditional identity.

If we all make what I can only believe would be the wrong choice, the tragedy of Toulouse and the hatred it represents will be the only winner. We must choose the fragile image of the flames over the secure image of community walls, which is nothing but an illusion.

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