PARIS — In early 21st century Europe, men, women and children are being killed for the sole reason that they are Jewish. These are not random attacks. They are targeted with precision and perpetrated against victims chosen for who they are, not for what they do or might have done.

The truth about the May 24 shooting at the Jewish Museum in Brussels is brutal and tragically simple. On the eve of the European Parliamentary elections, in the European Union's "capital" and just two weeks before the 70th anniversary of D-Day — a crucial step in the defeat of Nazism — anti-Semitism killed, again.

It will be up to a court to decide whether the Frenchman arrested yesterday in Marseille is responsible for last Saturday's killings. In mid-afternoon on that day, a man entered the Jewish Museum in Brussels' city center. He was carrying a bag from which he withdrew a gun before opening fire. He shot a dozen times before leaving, less than two minutes later. Four people were killed.

The events remind us of the March 19, 2012, crimes committed by Mohammed Merah at a Jewish school in the southern French city of Toulouse. He killed one teacher and three children in the school's playground because they were Jewish. As one girl tried to escape, Merah grabbed her by the hair and shot her in the head.

What's clear from both the Brussels and Toulouse shootings is that the pure racist hatred that is anti-Semitism is back.

The evidence strongly suggests that the suspect arrested Sunday is the killer. In his luggage, the police found an Kalashnikov assault rifle bearing inscriptions from a jihadist group fighting in Syria, a revolver, ammunition and a camera similar to that used by Merah to film and "sign" his crimes.

Like Merah, the young man seems to have combined gangsterism and jihadism, killing in the name of an al-Qaeda-inspired Islamist fight, for which Syria is the newest battlefield. He is said to have gone there for a year, like hundreds of other young Europeans, many of whom have north African origins. Syria has become a jihad training camp for these new terrorists.

The Internet, and more particularly Facebook, have served as recruitment and communication platforms. That's where jihadist groups broadcast their implausible ideological jumble, inspired by old-fashioned European anti-Semitism and conspiracy theories that flourish online. And these online meeting spaces are where they have resurrected the most horrific racist archetypes.

The liberalization of anti-Semitic rhetoric is a sign of the times, and it cannot simply be reduced to one or another geopolitical explanation. It is relayed by radical Islam and the diatribes of a too-famous French "humorist." Seeing it as mere police business would be like shirking our responsibilities.