MUNICH — At first glance, the video footage looks like a harmless Advent promotional clip. It showed cheerful people walking between decorated stalls, tinsels, Christmas trees, Santa hats. But back in 2000, the Strasbourg Christmas Market was already a prime target for terrorists, and this video was the most important piece of evidence against those suspected of plotting the attack. A man comments on the video in Arabic: "There we see the enemies of God strolling around," the voice says. "You will go to Hell, God willing."

In December 2000, four Algerians were arrested in Frankfurt, following a tip from Israel's secret service, the Mossad. German and French judges later ascertained that, a few months before the 9/11 attacks, this "Frankfurt cell" had planned to blow up a pressure cooker bomb. Two of the men had tried to defend themselves in court by saying the planned attack had in fact been intended to hit the Strasbourg synagogue, thus endangering the lives of fewer people than at the Christmas market.

There we see the enemies of God strolling around.

But time and time again, Christmas markets are targeted by terrorists. In Germany, the news from Strasbourg — where on Tuesday evening a man killed three and wounded 13 — has brought back bad memories. "In view of what happened, we in Berlin immediately think of the brutal terrorist attack on the Christmas market at Breitscheidplatz on December 19, two years ago," Berlin mayor Michael Müller said on Wednesday. A Tunisian Islamist had driven a truck into the crowd in the Berlin market, killing 12 people.

Berlin's Christmas market, a day after the Dec. 19, 2016 attack — Photo: Andreas Trojak

In November 2016, a planned attack on the Strasbourg Christmas market was feared, and police arrested seven men in Strasbourg and Marseille. And in December 2016, the Christmas market in Ludwigshafen, in the German state of Rhineland-Palatinate, was also targeted by a 12-year-old boy who had built an explosive device. Initially, he had planned to detonate it in a church, but an 18-year-old pulling the strings recommended, via the Telegram messenger service, that he hit the Christmas market instead. There, he told him, would be "many more people."

The only goal, as far as they're concerned, is to hit 'infidels.'

Ultimately, this is probably the main driving factor. In the cold European winter, there aren't many places where so many people gather in the open air. The many instructions to wannabe terrorists out there on the Internet contain cynical tips, with groups like ISIS recommending certain weapons and targets. You won't necessarily find special preferences for places with a religious Christian connotation. Neither the killer from Breitscheidplatz in Berlin nor the "Frankfurt cell" from the year 2000 were determined from the beginning that the target should necessarily be a Christmas market. The only goal, as far as they're concerned, is to hit "infidels" wherever there is an opportunity.

Since the attack from Breitscheidplatz could have inspired copycats, many Christmas markets in Germany have since been protected with concrete barriers and armed policemen. Now that Strasbourg has joined the list of victims, other cities will no doubt look to further tighten security at their open-air markets.

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