The investigation into last year's terrorist attacks at Brussels airport and subway revealed a well-organised group with clear links to illicit trade.
Jan Jambon, the country's deputy vice prime minister and minister of internal affairs, told the inaugural Economist Global Illicit Trade Summit this week that the terrorist cells are connected – both directly and indirectly – to large criminal networks, and this helps them operate under the radar of the authorities for prolonged periods.
"An enormous illegal economy has been created worldwide," said Jambon, who has served as Minister for of the Interior and Security for the last two-and-a-half years, adding: "It's not a coincidence that terrorist cells emerge at places where illicit trade is thriving."
A parallel universe has been created where flows of money from obscure sources allow terrorists to organise and fund themselves, and in many cases the individual terrorist operatives have been involved in crime from an early age, helping them learn the techniques that allow them to conduct their activities covertly.
The Molenbeek area of Brussels is a prime example of this, an area where high levels of unemployment, crime leading to incarceration and educational segregation have made it a fertile recruitment ground for terrorist organisations.
"In districts such as Molenbeek, the parallel economy at some point started to become so predominant that terrorism has been covered up both literally and figuratively, and impunity has become the norm," said Jambon.
"The battle against the illegal economy is therefore one of the great pillars of our so-called 'Canal plan', set up to challenge terrorism in nine districts around Brussels,"he added.
Key elements of the plan are to disrupt flows of money from illicit trade and deprive criminal and terrorist groups of the proceeds of crime and online criminal activities, and Belgium has boosted the headcount at its cybercrime division to help that effort.
"Given the worldwide ramifications of criminal networks, the international police cooperation is a priority that cannot be underestimated."