A Belgian soldier stands guard on a road leading to Zaventem airport after the attacks last week in Brussels, Belgium, March 29, 2016.
A Belgian soldier stands guard on a road leading to Zaventem airport after the attacks last week in Brussels, Belgium, March 29, 2016.
Francois Lenoir / Reuters

The attack in Brussels may have been shocking, but it was hardly surprising that Europe was subject to a coordinated terrorist campaign directed by the Islamic State (ISIS). As European officials reported in the days after the strike, ISIS had previously dispatched “at least 400 fighters to target Europe.” These terrorists, mostly of European origin, were instructed to construct “interlocking terror cells,” officials say, and were given autonomy to choose their target, timing, and methods. It is likely that the March bloodshed is not the last that Europe will see from these networks.

By now the pattern is well established. Fighters, after spending some time with ISIS proper in Syria or Iraq, return home to link up with brothers and childhood friends, who may have also made a pilgrimage to the Islamic State, and pals with whom they have forged bonds while learning to kill in Syria. They try to take the tactics of insurgency to the streets of Europe, killing civilians and targeting government installations. If they fail, they move on to the next plot. And if they succeed, they also move on to the next plot. 


Abdelhamid Abaaoud was the operations manager of the coordinated attacks on cafes, a stadium, and a concert hall in Paris on November 13, 2015. He should have been in prison at that point. In July 2015, he had been convicted and sentenced to 20 years in connection with another foiled plot in the Belgian city of Verviers. Some time between the foiled Verviers plots, in which two suspects died, and the Paris attack, Abaaoud managed to travel back to the Islamic State and then return to Europe later in 2015. From that point, the French government says, he coordinated four out of six foiled attacks targeting France since the spring.

Abaaoud was not the only man to walk away from last fall’s carnage in Paris. His old friend from Molenbeek, Salah Abdeslam, walked away, too, and returned to Brussels. Later analysis of Abaaoud’s telephone showed that, as the attacks unfolded in Paris on the night of November 13, Abaaoud was in constant touch with two phone numbers in Brussels. Who the contacts were became clear only after the Brussels attacks: they were the men who helped Abdeslam hide for four months in apartments that were rented using fake IDs. His arrest on March 18 set in motion the next chapter in the unfolding terrorist campaign with which Europe is now grappling.

A placard reading "I am alive" is seen among graffiti at a street memorial for the victims of bomb attacks in Brussels metro and Brussels international airport of Zaventem, in Brussels Belgium, March 28, 2016.
A placard reading "I am alive" is seen among graffiti at a street memorial for the victims of bomb attacks in Brussels metro and Brussels international airport of Zaventem, in Brussels Belgium, March 28, 2016.
Yves Herman / Reuters
The intricate network of connections between brothers, school friends, gang members, prison comrades, and an older generation of mentors from the heyday of Abu Musab al-Zarqawi’s al Qaeda in Iraq is as confusing as a long-running telenovela. One of the men who blew himself up in the airport in Brussels on Tuesday was identified as the maker of the suicide vests used in both Paris and Brussels. Now known to be Najim Laachraoui, he was previously known as “Soufiane Kayal.” Laachraoui was stopped in September at a border crossing between Hungary and Austria. Also in the car were Abdeslam and a man previously known as “Samir Bouzid.” They may have been returning to Europe from the Islamic State when they were stopped in September. It was “Kayal” and “Bouzid” whom Abaaoud was calling from Paris

“Bouzid” turned out to be Mohammed Belkaïd, an Algerian who lived in Sweden until April 2014, when he left his Swedish wife to sign up as a suicide bomber with ISIS. He was killed in a March 15th police raid on an apartment that Belkaïd shared with Abdeslam in the Forest district of Brussels. The apartment was rented in the name of one of the brothers responsible for the suicide bombings in Brussels. During the raid, authorities also found DNA traces belonging to Bilal Hadfi, one of the bombers who attacked the French stadium in November. 


After years of worrying about so-called lone wolf terrorism, it turns out that the really dangerous terrorists are thick as thieves. The high concentration of willing suicide bombers and mass killers in one small neighborhood is only understandable if violent extremism is viewed as a social virus that spreads by a process of complex contagion. Becoming a terrorist involves an act of volition—it is not contagious through mere contact. But close interactions among people belonging to different subgroups who embrace the same extremist belief system have a particular kind of contagious effect: they normalize the abnormal. And soon, large numbers are joining the cause.

Recruiting in the ISIS case is a three-step process. First there are the street preachers supplying the ideas. Laachraoui and Abaaoud belonged to a Belgian network led by Khalid Zerkani, a recruiter and street preacher operating out of Molenbeek. Prior to the Brussels attack, Laachraoui was tried in absentia in an ongoing trial in Belgium of 31 defendants accused of fighting for ISIS. All of them belonged to Zerkani’s group. Members of the Zerkani network were also linked to the 2015 Verviers plot, a conspiracy to kidnap and execute Belgian police that was coordinated by Abaaoud.

In addition to Zerkani, Abaaoud was involved with another major Belgian preacher, Fouad Belkacem, and his group, Sharia4Belgium. Belkacem and Zerkani are both in prison now. However, these two men—who are, in reality, gang leaders rather than preachers—have helped send at least 125 Belgians to fight alongside ISIS. Already, ISIS has already released videos in English, Flemish, and French taking responsibility for the Brussels attacks. The narrator in the videos is Hicham Chaib, a former gangster who formed Sharia4Belgium and was Belkacem’s bodyguard until Belkacem was imprisoned and Chaib went off to Syria. Chaib is a social media star for ISIS; in one particularly memorable Twitter thread, he posed with four decapitated heads

Second comes the near ubiquitous prison experience following involvement with drugs, gangs, and crime. Abaaoud was known as a regular user of alcohol and marijuana. The Abdeslam brothers were also stoners, and Saleh’s brother, Brahim, one of the Paris suicide bombers, was connected to the sale of illegal drugs. Abaaoud and Saleh Abdeslam were both convicted for armed robbery and may have cemented their relationship while in prison. The Bakraoui brothers had rap sheets that caused authorities to overlook the fact that they were also jihadists. Brahim, who blew himself up in the Brussels airport, was jailed for nine years for robbery involving a gun in 2010, and his brother, the Metro bomber, was given five years for carjacking in 2011. Belgium’s overcrowded penal system routinely releases convicted terrorists before they have completed their sentences. Other members of the extended Franco-Belgian network fall into this same pattern of pre-radicalization crime, including Mehdi Nemmouche, who served five years in prison for robbery before opening fire on the Jewish Museum in Brussels in 2014. 

The third step for the Brussels and Paris attackers was joining ISIS, which most of them did in early 2013. In the caliphate, brutality is a ritual. After the Verviers plot, ISIS released a recruitment video featuring Abaaoud grinning maniacally while driving a truck filled with dead bodies. After the Paris attacks, the group released a video featuring seven of the Paris cell members carrying out mass executions of unidentified victims—17 minutes of decapitations and full headshots. Having taken the lives of others in this gruesome manner, there would have been no way out.


The seriousness of the ISIS threat was driven home two days after the Brussels attacks, when it emerged that Belgian authorities had seized surveillance material from the apartment of a suspect linked to the Paris attack that indicated advanced preparations for an attack on a nuclear power plant on the Belgian-German border. The Bakraoui brothers who killed themselves in suicide attacks in Brussels on March 22 were part of the plot. The two men had been secretly videotaping one of the country's senior nuclear scientists. The discovery that the Belgian security services had been aware of the threat that terrorists may have been trying to acquire material for a “dirty bomb” came on the heels of news that one of the brothers had been caught in December trying to cross into Syria and was returned to Amsterdam by the Turkish authorities. The Dutch released him. This was just one of many intelligence failures that have already been revealed.

Broken windows of the terminal at Brussels airport are seen during a ceremony following bomb attacks in Brussels in Zaventem, Belgium, March 23, 2016.
Broken windows of the terminal at Brussels airport are seen during a ceremony following bomb attacks in Brussels in Zaventem, Belgium, March 23, 2016.
Yorick Jansens / Reuters
On Thursday, for example, French authorities arrested a man, Reda Kriket, who was convicted in absentia in July in connection with the Verviers plot. Kriket is another ISIS returnee and also belonged to the Zerkani network. Explosives were found in the raid and France announced that it had narrowly foiled another attack plot. The intended target is not known. The arrest in Paris set off another dramatic arrest in Brussels at a metro stop in Schaerbeek. Cell phone footage shows the police incapacitating a man who was waiting for the tram by shooting him in the leg. Video then shows a bombproof robot waddling in to pick up his backpack. The Belgian authorities have identified the man in custody only as Abderamane A., but press reports have identified him as Abderahmane Ameroud.

Amaroud was convicted in Belgium in 2005 for helping two Tunisians, also from Belgium, to assassinate Ahmed Shah Massoud, the Afghan opposition leader who was favored by the West. The killing took place the day before the 9/11 attacks and is seen as a favor from al Qaeda leader Osama bin Laden to Mullah Omar, the Taliban leader. In 2007, Ameroud was convicted yet again of terrorist activity, this time in connection with a camp set up in the Fontainebleau woods near Paris to train Frenchmen for battle in Iraq. Amaroud is another example of the inability of the Belgian judicial system to keep dangerous men locked up.

The European security services have failed badly. For now, blame has been heaped on Belgium. Terrorism is a federal responsibility in Belgium’s divided state and local authorities are apparently happy to do nothing. The New York Times cited the Molenbeek mayor saying that it was not her responsibility that there were terrorists living in her borough. Belgian ministers have tendered their resignations. A local police chief in the Flemish parts of Belgium north of Brussels had to admit that “a colleague forgot to pass on information” about Abdeslam’s whereabouts that might have led to his apprehension in December.

In recent days, arrests have been made in connection with the Brussels attacks and other suspected plots in The Netherlands and Germany, and in Italy a passport forger linked to both the Paris and the Brussels attackers was held when he went to a police station to obtain a residency permit. The playbook for the Belgian response days after the Brussels attacks comes straight from the French response to the Paris attacks, except that Brussels does not have the emergency powers that allowed the French to detain large numbers of subjects and to use house arrests as a means of controlling suspects. Thus, there will surely be another chapter in the unfolding story about intelligence failures. The Belgian judicial system moves slowly. Suspects charged with terrorism crimes are released to the street and expected to turn up for trial weeks, sometimes months later. And there are still mini-Molenbeeks in Gothenburg, Copenhagen, Vilvoorde, Melbourne, Antwerp, and the Paris suburbs—to name just a few. 

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