Forensic police investigate outside the building where raids took place in which several people, including Paris attacks suspect Salah Abdeslam, were arrested in Molenbeek, Belgium. The photo was taken on March 18. (Carl Court/Getty Images)

What’s the matter with Molenbeek?

Even before the March 22 bombings at Brussels’s Zaventem airport and the Maelbeek metro station, the Brussels neighborhood of Molenbeek had been linked to radical Islamist terrorism. One of 19 “communes” in the Brussels metro area, the neighborhood was home to one of the attackers in the 2004 commuter train bombings in Madrid and to the Frenchman who shot four people at the Jewish Museum in Brussels in August 2014. The Moroccan shooter on the Brussels-Paris Thalys train in August 2015 stayed with his sister there. French police suspect that the weapons used in the Paris supermarket attack connected with the Charlie Hebdo attack in January 2015 were acquired in Molenbeek, and the attackers in the November 2015 Paris bombings were traced to Brussels by way of a parking ticket issued on a rental car in Molenbeek.

How has this quarter of Brussels, populated in the 1970s by Moroccan immigrants with moderate Islamic beliefs, come to be Europe’s most notorious breeding ground for radical Islamist terrorism? Much of the answer lies in Brussels’s strange position in the Belgian federal system — a position that has encouraged political elites on both sides of Belgium’s politicized linguistic divide to ignore the brewing social discontents in one of the country’s poorest neighborhoods.

Molenbeek’s difficult demography and history

Statistically, Molenbeek is heavily Muslim and heavily immigrant. Fully 81 percent of the commune’s 100,000 residents are of foreign origin, and 41 percent are Muslim. It also has more than its share of social problems. In 2014, 27 percent of the working-age population, and 36 percent of those under 25, were unemployed.

Molenbeek is the second-poorest commune in Belgium, with 57 percent of the population living in poverty. Yet other poor, heavily Muslim immigrant neighborhoods in Europe — even those within Belgium targeted for anti-radicalization campaigns — don’t seem to be exporting terrorism at the same rate. What makes Molenbeek different?

The area’s distinct history helps. In the 1970s, goverments of Saudi Arabia and other Persian Gulf states sent funding for religious schools to Belgium, and the Belgian government provided mosques for Saudi-trained Wahabbi clerics in Molenbeek. Over the course of two generations, these clerics came to influence the area’s Moroccan- and Turkish-origin Muslim population. Jihadist activity in Brussels dates to the 1990s.

But Molenbeek’s problems go well beyond the specific history of radical Islam in the municipality, or the most recent history of mismanagement by longtime mayor Philippe Moureaux.

The problem with Belgium

Tim King of Politico argues that “Brussels’ nest of radicalism is one of the failings of a divided, dysfunctional country.” King focuses on the weakness of the relatively young and linguistically divided Belgian state, which he argues never really stamped out patronage and corruption. The result is a history of stalled reform and police and court systems that are too fragmented to work effectively to provide security or deliver justice.

King is onto something. The idiosyncratic structure of the Belgian state has clearly contributed to Molenbeek’s distinctive profile as a hotbed of radical Islam in Europe. But the real issues are of more recent vintage and tied to the process of decentralization of the Belgian state. The key moment that set Molenbeek on the path to its present state came in 1989, when a constitutional reform gave Belgium’s regions (Flanders, Wallonia and Brussels) and linguistic communities (Flemish, French and German) exclusive control over critical areas of policymaking.

These reforms divided governing authority in Belgium among three sources of power: the regions, which are territorially based and control matters of economic policy, employment, housing and other infrastructure; the communities, which are based on language and have competence in education, health care, welfare policy and integration of immigrants; and the federal government, which controls only residual, non-devolved powers, including foreign policy and criminal justice.

In most of Belgium, the regions and the communities are essentially merged, since most Flemish-speakers live in the Flanders region and most French-speakers in the Walloon region. The difficulty comes in Brussels, which is French by language, Flemish by geography (the city of Brussels is actually the capital of Flanders), and nobody’s first priority when it comes to providing services.

Why no one wants to invest in Brussels

In Brussels, the French and Flemish communities are in charge of education, cultural and social welfare matters. But in practice, Brussels is not always well served by either community. The French community has enough to do in Wallonia, which by virtue of its depressed economy generates less tax revenue and smaller budgets than does Flanders. And the Flemish community has little interest in social policy in what is fast becoming a French-speaking city.

As a result, residents of Brussels struggle to gain access to services — including active integration programs for migrants — that are enjoyed elsewhere in the country. In Flanders, immigrants receive language classes and courses about Belgian values, but the Flemish community does not offer such courses in Brussels.

Small wonder, then, that the mainly Arabic- and French-speaking residents of Molenbeek have trouble finding jobs in a city where even low-level service jobs require proficiency in both Dutch and French.

Furthermore, left to its own devices as a region to provide the infrastructure and services used by millions of daily commuters from Flanders and Wallonia, Brussels invests less than it needs into employment services, public housing, recreation centers, transportation and other forms of physical infrastructure that could aid integration.

For example, Brussels has one-seventeenth the amount of space for public recreation as do the cities of Namur, Leuven and Mechelen. One-fifth of working-age Bruxelloises depend on unemployment benefits or social assistance, yet unemployed youths are less likely to receive unemployment benefits in Brussels than in the Flemish region, and half of the families eligible for subsidized public housing are on waiting lists.

The bizarre form that Belgian federalism has taken thus exacerbates the disadvantage already faced by federal polities when coordinating law enforcement and security. The overlapping regional and community divisions mean that Brussels is a city where, despite its cosmopolitan veneer, political elites have little at stake.

Belgian elites are now shocked, shocked to discover that there is terrorism breeding in Molenbeek. Sadly, history offers little reason to hope that that will be enough to overcome the underlying causes of neglect that are built into the Belgian federal system.

Julia Lynch is an associate professor of political science at the University of Pennsylvania.