A European Union flag and a Belgian national flag fly at half mast for the victims of today's Brussels attacks in front of the Belgian embassy in Berlin, Germany, March 22, 2016.
Fabrizio Bensch / Reuters

It takes three hours to drive from Sint-Jans-Molenbeek in Brussels to Place de la République, a historic square in Paris. On Friday, November 13, three cars did just that. They were loaded with machine guns, ammunition, suicide vests, and three teams of trained guerillas from the Islamic State (also called ISIS). By midnight, the men from Molenbeek had killed 132 people and injured 350, setting a terrible new record for terrorist attacks perpetuated by European jihadists against their homeland.

Just days later, on Sunday night, French President François Hollande declared, “We are at war.” French fighter jets soon carried out bombing sorties over Raqqa, ISIS’ capital city, which is thousands of miles away from where the terrorists originated. So just who is France at war with? 

BACK TO BRUSSELS

On Monday morning, French officials released the name of the man they have identified as the mastermind of Friday’s attacks: Abdelhamid Abaaoud, a 27-year-old man born in the Molenbeek district in Brussels. Abaaoud is straight from central casting. He once posed in an ISIS propaganda video as the driver of a truck filled with mutilated bodies. He was also featured in an issue of Dabiq, ISIS’ glossy e-magazine, bragging about how he escaped a manhunt across Europe in January 2015 to find sanctuary in the caliphate. That month, ten days after the massacre at Charlie Hebdo, Belgian police had raided a cell of jihadists holed up in a house in Verviers, in easternBelgium. Apparently, the cell, which investigators say was linked to ISIS, had plans to kidnap and execute members of the Belgian police. Two members of the group died in a shootout with the police, and nine were later arrested in Molenbeek. But the leader—Abaaoud—got away. In July 2015, he was convicted in absentia and sentenced to 20 years in prison by a Belgian court. 

An undated photograph of a man described as Abdelhamid Abaaoud that was published in the Islamic State's online magazine Dabiq and posted on a social media website.
An undated photograph of a man described as Abdelhamid Abaaoud that was published in the Islamic State's online magazine Dabiq and posted on a social media website.
Reuters
Clearly, that didn’t deter him from planning a strike on Paris. Among last week’s attackers were three brothers from Molenbeek who were implicated in the Verviers cell and were already known to the police. One of the brothers was Salah Abdeslam. He reportedly drove a black Volkswagen Polo with Belgian registration plates that was found in front of the Bataclan concert hall, where 83 people were killed. He escaped the scene andreturned to Belgium early Saturday. He was stopped at the border but was allowed to drive on with two companions. He is now the subject of a manhunt. Ibrahim Abdeslam, another of the brothers, killed himself in front of a restaurant on Boulevard Voltaire near the Place de la République. His name was on the rental agreement of a Belgian-registered car that was found abandoned in the suburb of Montreuil, loaded with a cache machine guns and spent ammunition clips. The car was probably used in the drive-by shootings that killed 35 people in restaurants lining the Canal Saint-Matin near the Place de la République. A third brother, Mohamed Abdeslam, was arrested late Saturday in a sweep in Molenbeek but was later released. 

Police likewise already knew about the two other Frenchmen and Belgian who were identified as belonging to the attack team. Ismael Omar Mostefai, a 29-year-old French-Algerian born in a suburb of Paris, was the first attacker to be identified on Sunday. He committed suicide at the Bataclan nightclub after gunning down scores of people in the audience. In 2010, he had been given an “S notice,” a designation the French police use to indicate a person of interest, when he moved to the town of Chartres and became involved with a Salafist group. He went to Syria in the fall of 2013 and stayed through the spring of 2014. No information has emerged about where he has been more recently. Another Frenchman identified as Samy Amimour, 28, also blew himself up at the music hall. He faced an international arrest warrant on terrorism charges related to an incident in 2012 but he disappeared in 2013, joining ISIS. A final Belgian citizen, Bilal Hadfi, was one of the suicide bombers at the stadium. He lived in Belgium and investigators confirmed that he had fought with ISIS in Syria. Two of the terrorists have been identified as having lived in Molenbeek.

Finally, an attacker who blew himself up at the stadium was assumed to be the owner of a Syrian passport with the name Ahmad Almohammad from Idlib. The attacker is thought to have used the passport to enter Europe in early October, traveling with a second man. (Of course, the passport could have switched hands after the person who used it to get to Europe arrived.) The real identity of Ahmad Almohammad is not known, but it seems plausible that the forged passports were used by Belgians returning from the Islamic State

In the Paris attack, in other words, all roads lead to Brussels, specifically to Molenbeek, a neighborhood so notorious that even the Belgian minister in charge of the area admitted that it is at the crossroads of Europe’s problems with ISIS-inspired terrorism. Jan Jambon, the minister of home affairs and a Flemish nationalist, said on Sunday, “things were not under control in Molenbeek.” And the prime minister, Charles Michel, a Francophone liberal, went further and said, “This [Molenbeek] is a gigantic problem. Apart from prevention, we should also focus more on repression.”

COUNTERTERRORISM CHALLENGES

Belgian special forces police climb high on an apartment block during a raid, in search of suspected muslim fundamentalists linked to the deadly attacks in Paris, in the Brussels suburb of Molenbeek, November 16. 2015.
Belgian special forces police climb high on an apartment block during a raid, in search of suspected muslim fundamentalists linked to the deadly attacks in Paris, in the Brussels suburb of Molenbeek, November 16. 2015.
Yves Herman / Reuters
The danger in Molenbeek is nothing new. In June 2012, about a hundred members of Sharia4Belgium, a Belgian affiliate of the banned British organization al-Muhajiroun, attacked the Molenbeek police station during a riot related to the arrest of a woman who had refused police requests to remove her face veil. In February 2015, a court in Antwerp convicted 45 members of an Islamist group on terrorism-related offenses (the group had apparently tried to recruit for ISIS). Only eight showed up in the courtroom. The others had left for Syria. Abaaoud, the mastermind of Friday’s attacks, was also a member of Shara4Belgium.

Molenbeek is well known as a place for jihadists to meet and for French militants to flee when they do not want to go home. Mehdi Nemmouche, the terrorist who shot and killed four people in an attack outside the Jewish museum in Brussels in May 2014, found temporary refugee in Molenbeek after he returned from fighting with ISIS. Nemmouche was caught by happenstance at a bus station when, during a drug raid, the police found a machine gun in his luggage. After his arrest, Nemmouche confessed that he planned to go to Paris to carry out an attack on Bastille Day. The French-Moroccan terrorist Ayoub el-Khazzani, whose attempted August 2015 strike on a train from Brussels to Paris was averted by two American servicemen on vacation, also stopped over in Molenbeek on his way home from the Islamic State.

Also long-standing are worries about ISIS recruitment of Europeans. Indeed, French authorities have for some time warned that ISIS’ European recruitment was out of control. Official numbers vary, but it is believed that upward of a thousand French residents have joined ISIS, among them several hundred women. How many have returned is unclear. Estimates are around 250, but as Friday’s disaster showed, it is doubtful that the French authorities really know.

Europe’s open borders are another talking point, but open borders are an immutable fact of Europe. It is the failure to coordinate across divides that is the real problem. Long before the refugee crisis brought thousands upon thousands of desperate migrants to European soil, police and other officials responsible for tracking terrorists had already complained that the absence of routine information sharing or a Europe-wide registry of suspected radicals made their job impossible. That argument was heard again on Sunday. “We have open borders but not open information,” an unidentified Brussels-based diplomat told the Financial Times. “It’s not possible for that to continue.” The United Kingdom and Scandinavian countries harbor deep distrust about how some member states will use such registries. One more attack probably won’t sway them.  

An armed French gendarme stands along the highway as gendarmes check vehicles and verify the identity of travelers on the A1 motorway between Paris-Lille-Brussels near the Chaumont toll station, in France, November 16, 2015.
An armed French gendarme stands along the highway as gendarmes check vehicles and verify the identity of travelers on the A1 motorway between Paris-Lille-Brussels near the Chaumont toll station, in France, November 16, 2015.
Pascal Rossignol / Reuters
Impenetrable online communication is another frequently cited challenge. “It is a constant game of cat and mouse with electronic surveillance,” Camille Grand, a French counterterrorism expert, told the Daily Telegraph. “These groups moved from standard communications to encrypted files and then to using platforms like video gaming to communicate—it's a constant challenge keeping pace.” The Belgian home affairs minister revealed over the weekend that the Paris attackers used PlayStation 4 for messaging.

Still, electronic surveillance has been remarkably successful; so successful, in fact, that too much emphasis is placed in it. Days before the Paris disaster, online surveillance led to the coordinated arrest of suspects linked to a terrorist network run from prison by Mullah Krekar, a Norway-based Iraqi-Kurdish founder of Ansar al-Islam. A dozen suspects were picked up in Italy, four in Britain, and three in Norway. Krekar’s group has reemerged as Rawti Shax and has pledged affiliation with ISIS. Police say that some suspected members had travelled to Syria or Iraq. Members are allegedly responsible for a great deal of the Europe-based social media activity supporting ISIS.

The effectiveness of online surveillance helped encourage the fallacy that you can catch terrorists online. But terrorists organize in real life. Often they have grown up together, are brothers or neighbors, and trust each other because they communicate face to face. Online networks trail the ones forged in person. When terrorists have big plans, they “go dark” for months before executing their plans. 

A view shows the bar Les Beguines, in Molenbeek, November 16, 2015. Documents show that the bar was run by the French Abdeslam brothers, one of whom blew himself up in Paris on Friday night.
A view shows the bar Les Beguines, in Molenbeek, November 16, 2015. Documents show that the bar was run by the French Abdeslam brothers, one of whom blew himself up in Paris on Friday night.
Eric Vidal / Reuters
BORDER WAR

All this points to what Europe does and doesn’t need to do in response to the attack. Bombing Raqqa will not touch the hubs of networked militants who, despite living in Molenbeek, Lunel, or Luton—small towns and neighborhoods that have become infamous for the large number of young men and women who have traveled to Syria—see themselves as denizens of the Islamic State. If these foreign fighters have not already returned home—or to Molenbeek—they will start to return as France and the United States drop more bombs on Raqqa and the other residential areas of the Islamic State. 

What Europe does need to do is set up controls on its outer borders. It does need to share information about the identities of suspected militants who have traveled to or attempted to travel to the multiplying sites of insurgency in Africa, the Middle East, and Asia. It needs to start arresting and trying suspected militants; only a fraction of the individuals known to have traveled to take part in insurgencies abroad have been arrested and tried, even though joining a terrorist organization is a criminal offense. Squeamish about facing up to disbelieving judges and protesting advocacy organizations, European leaders have dodged their obligations. 

Terrorists from Europe are combatants in a global war that threatens the West, the lives of the people they help terrorize abroad, and the stability of Muslim countries. The best chance of doing something is to arrest the terrorists when they are at home and incarcerate them long enough, and far enough away from their friends and coconspirators, that they give up the war. The West must fight in court, in neighborhoods, and in compulsory programs that separate young people who have not yet committed serious offenses from ISIS’ pied pipers. This war starts—and will end—at home.

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  • JYTTE KLAUSEN is the Lawrence A. Wien Professor of International Cooperation at Brandeis University and an Affiliate at the Center for European Studies at Harvard University.
  • More By Jytte Klausen