As more than a thousand Westerners have joined the conflict in Iraq and Syria, the highest number per-capita have come from Belgium, according to an analysis by Business Insider.
Between 250 and 400 jihadists in the area are thought to have come from the small European nation, which has a population of 11 million.
Although the trend may seem surprising from a highly developed state known for waffles and EU bureaucracy, a closer look at Belgium's fractured society shows this may have been a long time coming.
Failed Integration
Muslim immigrants are not well integrated into Belgian society despite decades of immigration from countries like Tunisia, Morocco, Turkey and Algeria.
While Muslim Belgians make up only 4-6% of the country's population, some politicians say their very presence threatens the Belgian way of life.
Wearing a face veil can earn you a $200 fine in Belgium, and far-right anti-immigrant political groups have achieved healthy levels of support.
Vlaams Belang, a Flemish political party which has advocated deporting Muslim immigrants who don't renounce their faith, has achieved upwards of 20% of the vote in some regional elections.
In 2013, the Minister for Integration and current leader of the Flemish government, Geert Bourgeois, spoke about a report which showed less than a third of young Muslims felt accepted by Flemish society.
"That so many young people are discriminated against or feel rejected means we have a lot of work to do as a society," he said, "but another way of looking at it could be that we think young Muslims do not belong to because they do not want to belong."
With a population so divided, Belgian Muslims tend to live in close-knit communities with seperate social circles. Without integration, radical groups can take root.
Belgium is home to the banned extremist Salafist group, Sharia4Belgium, which remains active underground. The group supports ISIS and is accused of recruiting fighters for the war in Syria.
Abu Hanifa al Belgiki, a former bodyguard for Sharia4Belgium's leader, recently appeared in an ISIS video claiming that since taking up arms in Syria, he has "never felt so Muslim."
Prosecutors - who have charged 46 members of the group - say Sharia4Belgium has links to international jihadi groups and is responsible for a significant proportion of Belgium's jihadi outflow.
Government Response
In a recent New York Times op-ed, two Belgian Arab-experts wrote that few of the Belgian jihadis would qualify as radical Islamists when they left the country, with most being driven by idealism.
"What most have in common, apart from their with to help fellow believers, is a disillusionment with the West's attitude toward Muslims," authors note.
The article notes that the Belgian government has done little to address concerns over unemployment, discrimination and economic deprivation in the Islamic the community.
Doctor Sara Silvestri, an expert in Islamism and international politics at City University London, told Business Insider that in an age of live news, trans-national communication and mixed identities, "it cannot be surprising to find out that people in one country feel attracted to the cause of another."
"This does not mean necessarily that people who decide to go to Syria or Iraq automatically nourish sentiments against their original countries of birth or of residence though."
Silvestri said that Western governments face tough balancing acts in combatting potential threats with harsher laws: "Policymakers are stuck in a dilemma whereby if they act in one way they secure the trust of the majority of the population but then run a high risk of alienating for good their Muslim minorities, thus playing into the hands of ISIS."
"On the other hand, if they try to appeal to social cohesion and harmony between communities they could run up against the growing political competition of right wing parties, which are very canny in deploying anti-Muslim and anti-immigrant discourse," she said.
Governments in the U.K., the Netherlands, and Australia have sought to combat extremist Islamism by fostering better relations with moderate Islamic leaders, as well as increasing surveillance levels and canceling passports.
Silvestri warned that some measures may risk stigmatizing communities, describing the cancellation of passports as "a big gift to Islamic State and its claim to be a sovereign state with its own citizens."
Deciding when to take action is also a challenge "when the line between what constitutes evidence of a crime and mere suspicion or assumption is very thin," she said.
"Rather than becoming concerned with one particular country as the generator of radical jihadist we ought to be preoccupied more for the protraction of the conflict itself in Syria and for the way in which this has shaken Muslim feelings globally," Silvestri said. "If the international community had coalesced and done something about it some years ago we would not be in this situation now."
For more details on how ISIS is recruiting Western fighters, you can read our full report on Western jihadis here.