A RUSI analysis 'Thick As Thieves: European Criminals Take to Syria’s Battlefield' by Rafaello Pantucci, raises an issue we should discuss.

His sub-title is:
Individuals with known criminal histories are a surprisingly common feature of the current Syrian battlefield. While their motives may be a combination of redemption and opportunism, returnees in this mode pose a complicated threat picture for security services to process if they return.
He ends with:
The terror-crime nexus is not a new one. People with criminal pasts are often drawn to extremist ideologies as a way of atoning for past sins, though often they donot leave their pasts completely behind. But the high instance of people going to Syria with criminal pasts of every sort adds a further worrying dimension to the phenomenon of foreign fighters going to Syria.
Link:https://www.rusi.org/analysis/commen.../#.Uzlj0ahdXk_

Much of the SWC discussion around 'foreign fighters' currently is on another thread 'Foreign fighters in Syria: a crime minus a motive?', but IIRC we have not debated this issue before. I do concede reference has been made in virtually all regional conflicts to crime and terrorism, not in the context of 'foreign fighters' returning home in the West.

In the UK context it has been very clear that there is little relationship between criminal activity, criminals and organised crime with domestic Jihadi terrorism. 'The Troubles' in Northern Ireland were and are quite different, on both sides it was very hard to see any distinction, especially when it came to money raising.